10/16/2010




                                  Capacity and Constraint                                                                    Outline
    S7                                Management
                                                                                             Capacity
                                                                                                       Design and Effective Capacity
                                                                                                       Capacity and Strategy
   PowerPoint presentation to accompany
   Heizer and Render                                                                                   Capacity Considerations
   Operations Management, 10e
   Principles of Operations Management, 8e                                                             Managing Demand
   PowerPoint slides by Jeff Heyl                                                                      Demand and Capacity
                                                                                                       Management in the Service Sector


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                          Outline – Continued                                                    Outline – Continued
                     Bottleneck Analysis and Theory of                                      Reducing Risk with Incremental
                     Constraints                                                            Changes
                                Process Times for Stations,                                 Applying Expected Monetary
                                Systems, and Cycles                                         Value to Capacity Decisions
                                Theory of Constraints                                       Applying Investment Analysis to
                                Bottleneck Management                                       Strategy-Driven Investments
                     Break-Even Analysis                                                               Investment, Variable Cost, and
                                Single-Product Case                                                    Cash Flow
                                Multiproduct Case                                                      Net Present Value

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                          Learning Objectives                                                    Learning Objectives
          When you complete this supplement,                                     When you complete this supplement,
          you should be able to:                                                 you should be able to:
             1. Define capacity                                                     5. Determine the expected monetary
             2. Determine design capacity, effective                                   value of a capacity decision
                capacity, and utilization                                           6. Compute net present value
             3. Perform bottleneck analysis
             4. Compute break-even analysis



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                            Process Strategies                                                                                                                       Capacity
                                                                                                                                   The throughput, or the number of
           The objective of a process strategy is                                                                                  units a facility can hold, receive,
            to build a production process that                                                                                     store, or produce in a period of time
            meets customer requirements and
                                                                                                                                   Determines
                                                                                                                                     ete    es
            product specifications within cost
                                                                                                                                   fixed costs
             and other managerial constraints
                                                                                                                                   Determines if
                                                                                                                                   demand will
                                                                                                                                   be satisfied
                                                                                                                                   Three time horizons
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                       Planning Over a Time                                                                                                Design and Effective
                             Horizon                                                                                                            Capacity
                                                         Options for Adjusting Capacity

  Long-range                      Add facilities
                                                                                                                                 Design capacity is the maximum
  planning                        Add long lead time equipment              *                                                    theoretical output of a system
  Intermediate-                   Subcontract                                Add personnel
  range                           Add equipment                              Build or use inventory                                        Normally expressed as a rate
                                                                                                                                           N    ll          d        t
  planning                        Add shifts
                                                                                                                                 Effective capacity is the capacity a
  Short-range
                                                                            Schedule jobs
                                                                                                                                 firm expects to achieve given current
  planning
                                                                        *   Schedule personnel
                                                                            Allocate machinery
                                                                                                                                 operating constraints
                                               Modify capacity                  Use capacity
                                                                                                                                           Often lower than design capacity
    * Difficult to adjust capacity as limited options exist
                                                                                          Figure S7.1
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               Utilization and Efficiency                                                                                                           Bakery Example

       Utilization is the percent of design capacity                                                                          Actual production last week = 148,000 rolls
       achieved                                                                                                               Effective capacity = 175,000 rolls
                                                                                                                              Design capacity = 1,200 rolls per hour
                  Utilization = Actual output/Design capacity
                                          p       g    p    y                                                                 Bakery operates 7 days/week, 3 - 8 hour shifts


       Efficiency is the percent of effective capacity                                                                    Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls
       achieved

                Efficiency = Actual output/Effective capacity


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                                  Bakery Example                                                              Bakery Example

            Actual production last week = 148,000 rolls                                 Actual production last week = 148,000 rolls
            Effective capacity = 175,000 rolls                                          Effective capacity = 175,000 rolls
            Design capacity = 1,200 rolls per hour                                      Design capacity = 1,200 rolls per hour
            Bakery operates 7 days/week, 3 - 8 hour shifts                              Bakery operates 7 days/week, 3 - 8 hour shifts


        Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls                     Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls

                                                                                                      Utilization = 148,000/201,600 = 73.4%




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                                  Bakery Example                                                              Bakery Example

            Actual production last week = 148,000 rolls                                 Actual production last week = 148,000 rolls
            Effective capacity = 175,000 rolls                                          Effective capacity = 175,000 rolls
            Design capacity = 1,200 rolls per hour                                      Design capacity = 1,200 rolls per hour
            Bakery operates 7 days/week, 3 - 8 hour shifts                              Bakery operates 7 days/week, 3 - 8 hour shifts


        Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls                     Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls

                          Utilization = 148,000/201,600 = 73.4%                                       Utilization = 148,000/201,600 = 73.4%

                                                                                                      Efficiency = 148,000/175,000 = 84.6%

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                                  Bakery Example                                                              Bakery Example

            Actual production last week = 148,000 rolls                                 Actual production last week = 148,000 rolls
            Effective capacity = 175,000 rolls                                          Effective capacity = 175,000 rolls
            Design capacity = 1,200 rolls per hour                                      Design capacity = 1,200 rolls per hour
            Bakery operates 7 days/week, 3 - 8 hour shifts                              Bakery operates 7 days/week, 3 - 8 hour shifts
                                                                                        Efficiency = 84.6%
                                                                                        Effi i       84 6%
                                                                                        Efficiency of new line = 75%
        Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls
                                                                                      Expected Output = (Effective Capacity)(Efficiency)
                          Utilization = 148,000/201,600 = 73.4%
                                                                                                                                = (175,000)(.75) = 131,250 rolls
                          Efficiency = 148,000/175,000 = 84.6%

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                                  Bakery Example                                                                                      Capacity and Strategy

            Actual production last week = 148,000 rolls                                                                              Capacity decisions impact all 10
            Effective capacity = 175,000 rolls
            Design capacity = 1,200 rolls per hour                                                                                   decisions of operations
            Bakery operates 7 days/week, 3 - 8 hour shifts                                                                           management as well as other
            Efficiency = 84.6%
            Effi i       84 6%                                                                                                       functional areas of the organization
                                                                                                                                     f   ti   l        f th       i ti
            Efficiency of new line = 75%
                                                                                                                                     Capacity decisions must be
          Expected Output = (Effective Capacity)(Efficiency)                                                                         integrated into the organization’s
                                                    = (175,000)(.75) = 131,250 rolls                                                 mission and strategy


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                Capacity Considerations                                                                                                 Economies and
                                                                                                                                     Diseconomies of Scale
        1. Forecast demand accurately
                                                                                                      (dollars per room per night)



        2. Understand the technology and
                                                                                                           Average uni cost




           capacity increments
             p    y                                                                                                                      25 - room                                 75 - room
                                                                                                                       it




                                                                                                                                      roadside motel                            roadside motel
                                                                                                                      m




                                                                                                                                                                 50 - room
        3. Find the optimum                                                                                                                                   roadside motel

           operating level
           (volume)
                                                                                                                                                Economies               Diseconomies
        4. Build for change                                                                                                                      of scale                  of scale
                                                                                                                                           25                  50                      75
                                                                                                                                                         Number of Rooms
                                                                                                                                                                                         Figure S7.2
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                             Managing Demand                                                                                         Complementary Demand
                   Demand exceeds capacity
                                                                                                                                           Patterns
                             Curtail demand by raising prices,
                             scheduling longer lead time
                             Long term solution is to increase capacity                                                   4,000 –
                                                                                                         Sales in units




                   Capacity exceeds demand                                                                                3,000 –

                             Stimulate market                                                                             2,000 –
                             Product changes                                                                                                                                            Jet ski
                                                                                                                          1,000 –
                                                                                                                                                                                        engine
                   Adjusting to seasonal demands                                                                                                                                        sales

                             Produce products with complementary                                                                      JFMAMJJASONDJFMAMJJASONDJ
                             demand patterns                                                                                                   Time (months)
                                                                                                                                                                                            Figure S7.3
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                         Complementary Demand                                                                                 Complementary Demand
                               Patterns                                                                                             Patterns
                                                                                                                                                                  Combining both
                                                                                                                                                                  demand patterns
                                                                                                                                                                  reduces the
                                                                                                                                                                  variation
                       4,000 –                                                                                              4,000 –
      Sales in units




                                                                                                           Sales in units
                                                                             Snowmobile
                                                                             S       bil                                                                             Snowmobile
                                                                                                                                                                     S       bil
                       3,000 –                                               motor sales                                    3,000 –                                  motor sales

                       2,000 –                                                                                              2,000 –

                       1,000 –                                                Jet ski                                       1,000 –                                   Jet ski
                                                                              engine                                                                                  engine
                                                                              sales                                                                                   sales

                             JFMAMJJASONDJFMAMJJASONDJ                                                                            JFMAMJJASONDJFMAMJJASONDJ
                                      Time (months)                                                                                        Time (months)
                                                                               Figure S7.3                                                                              Figure S7.3
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                                 Tactics for Matching                                                                           Demand and Capacity
                                 Capacity to Demand                                                                              Management in the
                   1. Making staffing changes
                                                                                                                                   Service Sector
                   2. Adjusting equipment                                                                                     Demand management
                                 Purchasing additional machinery                                                                      Appointment, reservations, FCFS rule
                                 Selling or leasing out existing equipment
                   3. Improving processes to increase throughput                                                              Capacity
                   4. Redesigning products to facilitate more
                                                                                                                              management
                      throughput                                                                                                      Full time,
                   5. Adding process flexibility to meet changing                                                                     temporary,
                      product preferences                                                                                             part-time
                   6. Closing facilities                                                                                              staff
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                          Bottleneck Analysis and                                                                    Process Times for Stations,
                           Theory of Constraints                                                                        Systems, and Cycles
                          Each work area can have its own unique                                                                  The process time of a station is the
                          capacity                                                                                                time to produce a unit at that single
                          Capacity analysis determines the                                                                        workstation
                          throughput capacity of workstations in a                                                                The process time of a system is the
                          system                                                                                                  time of the longest process in the
                          A bottleneck is a limiting factor or                                                                    system … the bottleneck
                          constraint                                                                                              The process cycle time is the time it
                          A bottleneck has the lowest effective                                                                   takes for a product to go through the
                          capacity in a system                                                                                    production process with no waiting
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                                                                                                                                                                Process Times for Stations,
       A Three-Station
         Three-                                                                                                                                                    Systems, and Cycles
       Assembly Line
                                                                                                                                                                              The system process time is the
                                                                                                       QuickTime™ and a
                                                                                                         decompressor
                                                                                                are needed to see this picture.




                                                                                                                                                                              process time of the bottleneck after
                                                                                                                                                                              dividing by the number of parallel
                                                                                                                                                                              operations
                                                                                                                                                                              The system capacity is the inverse
                   A                                                B                                                             C                                           of the system process time
           2 min/unit                                          4 min/unit                                          3 min/unit                                                 The process cycle time is the total
                                                                                                                                                                              time through the longest path in the
                                                                                                                     Figure S7.4                                              system

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                                                                                                                                                               Capacity                                                                  Bread              Fill              Toast

                              Capacity Analysis                                                                                                                Analysis                                                Order
                                                                                                                                                                                                                      30 sec
                                                                                                                                                                                                                                        15 sec             20 sec             40 sec
                                                                                                                                                                                                                                                                                                Wrap
                                                                                                                                                                                                                                                                                               37.5 sec
                                                                                                                                                                                                                                         Bread              Fill              Toast
                                                                                                                                                                                                                                        15 sec             20 sec             40 sec

               Two identical sandwich lines
                                                                                                                                                                      Toast work station has the longest processing
               Lines have two workers and three operations                                                                                                            time – 40 seconds
               All completed sandwiches are wrapped                                                                                                                   The two lines each deliver a sandwich every 40
                                                                                                                                                                      seconds so the process time of the combined
                                                                                                                                                                                       p
                                                                                                                                                                      lines is 40/2 = 20 seconds
                                    Bread                         Fill                 Toast
                                                                                                                                                                      At 37.5 seconds, wrapping and delivery has the
       Order
                              15 sec/sandwich                20 sec/sandwich       40 sec/sandwich
                                                                                                                                      Wrap
                                                                                                                                                                      longest processing time and is the bottleneck
30 sec/sandwich                                                                                                               37.5 sec/sandwich                       Capacity per hour is 3,600 seconds/37.5
                                    Bread                         Fill                 Toast                                                                          seconds/sandwich = 96 sandwiches per hour
                              15 sec/sandwich                20 sec/sandwich       40 sec/sandwich
                                                                                                                                                                      Process cycle time is 30 + 15 + 20 + 40 + 37.5 =
                                                                                                                                                                      142.5 seconds
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                                                                                                                                                               Capacity                                                                                            Cleaning




                              Capacity Analysis                                                                                                                Analysis
                                                                                                                                                                                                                     Check
                                                                                                                                                                                                                       in

                                                                                                                                                                                                                    2 min/unit
                                                                                                                                                                                                                                   Takes
                                                                                                                                                                                                                                   X-ray

                                                                                                                                                                                                                                 2 min/unit
                                                                                                                                                                                                                                              Develops
                                                                                                                                                                                                                                               X-ray

                                                                                                                                                                                                                                              4 min/unit
                                                                                                                                                                                                                                                               24 min/unit


                                                                                                                                                                                                                                                                    X-ray
                                                                                                                                                                                                                                                                    exam
                                                                                                                                                                                                                                                                                   Dentist


                                                                                                                                                                                                                                                                                  8 min/unit
                                                                                                                                                                                                                                                                                                  Check
                                                                                                                                                                                                                                                                                                   out

                                                                                                                                                                                                                                                                                                6 min/unit


                                                                                                                                                                                                                                                               5 min/unit

               Standard process for cleaning teeth
                                                                                                                                                                      All possible paths must be compared
               Cleaning and examining X-rays can happen
               simultaneously                                                                                                                                         Cleaning path is 2 + 2 + 4 + 24 + 8 + 6 = 46
                                                                                                                                                                      minutes
                                                                                                                                                                      X-ray exam path is 2 + 2 + 4 + 5 + 8 + 6 = 27
                                                                         Cleaning                                                                                     minutes
                           Takes              Develops                   24 min/unit                                                   Check                          Longest path involves the hygienist cleaning the
  Check in                                                                                     Dentist
                           X-ray               X-ray                                                                                    out                           teeth
  2 min/unit            2 min/unit            4 min/unit                   X-ray               8 min/unit                             6 min/unit                      Bottleneck is the hygienist at 24 minutes
                                                                           exam
                                                                                                                                                                      Hourly capacity is 60/24 = 2.5 patients
                                                                         5 min/unit
                                                                                                                                                                      Patient should be complete in 46 minutes
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                      Theory of Constraints                                                         Bottleneck Management
             Five-step process for recognizing and                                     1. Release work orders to the system at the
             managing limitations                                                         pace of set by the bottleneck
             Step 1: Identify the constraint                                           2. Lost time at the bottleneck represents
             Step 2: Develop a plan for overcoming the
                p          p p                   g                                                                 y
                                                                                          lost time for the whole system
                     constraints                                                       3. Increasing the capacity of a non-
             Step 3: Focus resources on accomplishing Step 2                              bottleneck station is a mirage
             Step 4: Reduce the effects of constraints by                              4. Increasing the capacity of a bottleneck
                     offloading work or expanding capability                              increases the capacity of the whole
             Step 5: Once overcome, go back to Step 1 and find                            system
                     new constraints

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                        Break-
                        Break-Even Analysis                                                                      Break-
                                                                                                                 Break-Even Analysis
                                                                                                 Fixed costs are costs that continue
                   Technique for evaluating process                                              even if no units are produced
                   and equipment alternatives
                                                                                                                  Depreciation, taxes, debt, mortgage
                   Objective is to find the point in                                                              payments
                   dollars and units at which cost                                               Variable costs are costs that vary
                   equals revenue                                                                with the volume of units produced
                   Requires estimation of fixed costs,                                                            Labor, materials, portion of utilities
                   variable costs, and revenue                                                                    Contribution is the difference between
                                                                                                                  selling price and variable cost

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                        Break-
                        Break-Even Analysis                                                                      Break-
                                                                                                                 Break-Even Analysis
                                                                                                                   –
        Assumptions                                                                                             900 –
                                                                                                                                                                        Total revenue line


            Costs and revenue are linear                                                                        800 –
                                                                                                                            Break-even point                                  Total cost line
            functions                                                                                           700 –   Total cost = Total revenue
                                                                                              Cost in dollars




                                                                                                                600 –
                                     Generally not the case in the
                                              y
                                                                                                      d




                                                                                                                500 –
                                     real world
                                                                                                                400 –                                              Variable cost

                          We actually know these costs                                                          300 –

                                     Very difficult to verify                                                   200 –

                                                                                                                100 –                                              Fixed cost
                          Time value of money is often                                                             –
                                                                                                                   |     |   |     |        |   |   |   |    |      |     |     |

                          ignored                                                                                  0    100 200 300 400 500 600 700 800 900 1000 1100
                                                                                Figure S7.5                                            Volume (units per period)

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                         Break-
                         Break-Even Analysis                                                                                                      Break-
                                                                                                                                                  Break-Even Analysis
                  BEPx = break-even point in                               x = number of units                                        BEPx = break-even point in                                x = number of units
                         units                                                 produced                                                      units                                                  produced
                  BEP$ = break-even point in                             TR  = total revenue = Px                                     BEP$ = break-even point in                             TR   = total revenue = Px
                         dollars                                          F  = fixed costs                                                   dollars                                          F   = fixed costs
                     P = price per unit (after                            V  = variable cost per unit                                    P = price per unit (after                            V   = variable cost per unit
                         all discounts)                                  TC  = total costs = F + Vx                                          all discounts)                                  TC   = total costs = F + Vx

                                                                                                                                     BEP$ = BEPx P
        Break-
        Break-even point occurs when
                                                                                                                                          = F P                                                 Profit = TR - TC
                                                                                                                                            P-V                                                        = Px - (F + Vx)
                      TR = TC                                                                  F                                                F
                         or                                                       BEPx =                                                  =                                                            = Px - F - Vx
                                                                                              P-V                                           (P - V)/P
                     Px = F + Vx                                                                                                               F                                                       = (P - V)x - F
                                                                                                                                          =
                                                                                                                                            1 - V/P
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                         Break-
                         Break-Even Example                                                                                                       Break-
                                                                                                                                                  Break-Even Example

   Fixed costs = $10,000                                              Material = $.75/unit                                   Fixed costs = $10,000                                         Material = $.75/unit
   Direct labor = $1.50/unit                                          Selling price = $4.00 per unit                         Direct labor = $1.50/unit                                     Selling price = $4.00 per unit

                                           F                $10,000                                                                                                  F                $10,000
                      BEP$ =                     =                                                                                           BEP$ =                        =
                                       1 - (V/P)   1 - [(1.50 + .75)/(4.00)]                                                                                     1 - (V/P)   1 - [(1.50 + .75)/(4.00)]
                                                                                                                                                                  $10,000
                                                                                                                                                           =              = $22,857.14
                                                                                                                                                                   .4375

                                                                                                                                                                   F         $10,000
                                                                                                                                              BEPx =                  =                     = 5,714
                                                                                                                                                                  P-V   4.00 - (1.50 + .75)

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                         Break-
                         Break-Even Example                                                                                                       Break-
                                                                                                                                                  Break-Even Example
                   50,000 –
                                                                                                                                 Multiproduct Case
                                                                                          Revenue
                   40,000 –
                                                                                                                                                                                                F
                                                       Break-even                                                                                                BEP$ =
                                                          point
                   30,000 –                                                                             Total
                                                                                                                                                                                       ∑   1-
                                                                                                                                                                                                Vi
                                                                                                                                                                                                   x (Wi)
        Dollars
              s




                                                                                                        costs
                                                                                                           t
                                                                                                                                                                                                Pi
                   20,000 –

                                                                                          Fixed costs                                 where             V      = variable cost per unit
                   10,000 –
                                                                                                                                                        P      = price per unit
                                                                                                                                                        F      = fixed costs
                          –
                          |                 |                  |            |         |             |
                                                                                                                                                        W      = percent each product is of total dollar sales
                          0             2,000                4,000        6,000     8,000      10,000
                                                                     Units
                                                                                                                                                         i     = each product

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                      Multiproduct Example                                                                                             Multiproduct Example
              Fixed costs = $3,000 per month                                                                                     Fixed costs = $3,000 per month
                                                                              Annual Forecasted                                                                                                       Annual Forecasted
              Item                                Price            Cost          Sales Units                                     Item                                 Price          Cost                Sales Units
              Sandwich                            $5.00            $3.00            9,000                                        Sandwich                             $5.00          $3.00                  9,000
              Drink                                1.50              .50            9,000                                        Drink                                 1.50            .50                  9,000
              Baked potato                         2.00
                                                   2 00             1.00
                                                                    1 00            7,000
                                                                                    7 000                                        Baked potato                          2.00
                                                                                                                                                                       2 00           1.00
                                                                                                                                                                                      1 00                  7,000
                                                                                                                                                                                                            7 000

                                                                                                                                                                           Annual           Weighted
                                                                                                                                        Selling Variable                 Forecasted % of Contribution
                                                                                                                     Item (i)          Price (P) Cost (V) (V/P) 1 - (V/P) Sales $   Sales (col 5 x col 7)
                                                                                                                  Sandwich                $5.00          $3.00                 .60   .40            $45,000       .621        .248
                                                                                                                  Drinks                   1.50            .50                 .33   .67             13,500       .186        .125
                                                                                                                  Baked                    2.00           1.00                 .50   .50             14,000       .193        .096
                                                                                                                   potato
                                                                                                                                                                                                    $72,500      1.000        .469

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                      Multiproduct Example  F
                                                                                                                                         Reducing Risk with
                                BEP =
                                      ∑ 1 - P x (W )
                                            V
                                                                       $
                                                                                     i
                                                                                              i
                                                                                                                                        Incremental Changes
              Fixed costs = $3,000 per month                                         i
                                                                                                                            (a) Leading demand with                                            (b) Capacity lags demand with
                                                                                                                                incremental expansion                                              incremental expansion
                                                                           $3,000 x Forecasted
                                                                            Annual 12
                                                                                                                                                                                                        New
              Item                                Price            Cost =       Sales Units
                                                                                         = $76,759                                 New
                                                                               .469                                              capacity                                                             capacity
                                                                                                                        Demand




              Sandwich                            $5.00            $3.00            9,000




                                                                                                                                                                                           Demand
                                                                                                                                                                   Expected                                                Expected
                                                                                                                                                                   demand                                                  demand
              Drink                                1.50              .50
                                                                     Daily          9,000
                                                                              $76,759
              Baked potato                         2.00
                                                   2 00             1sales = 312 days = $246.02
                                                                    1.00
                                                                      00            7 000 $246 02
                                                                                    7,000

                                               Annual           Weighted
           Selling Variable                .621 x $246.02 of Contribution
                                             Forecasted %                                                                                                    (c) Attempts to have an average
    Item (i)
          Price (P) Cost (V) (V/P) 1 - (V/P) Sales $      = 30.6 ≈ 31
                                                        Sales (col 5 x col 7)                                                                                    capacity with incremental
                                                $5.00      sandwiches                                                                                            expansion
 Sandwich   $5.00    $3.00     .60     .40    $45,000   .621 per day
                                                                   .248
                                                                                                                                                                      New
 Drinks      1.50      .50     .33     .67     13,500   .186       .125
                                                                                                                                                          Demand




                                                                                                                                                                    capacity               Expected
 Baked       2.00     1.00     .50     .50     14,000   .193       .096                                                                                                                    demand
  potato
                                              $72,500 1.000        .469

                                                                                                                                                                                                                         Figure S7.6
© 2011 Pearson Education, Inc. publishing as Prentice Hall                                             S7 - 51   © 2011 Pearson Education, Inc. publishing as Prentice Hall                                                            S7 - 52




                        Reducing Risk with                                                                                               Reducing Risk with
                       Incremental Changes                                                                                              Incremental Changes
                               (a) Leading demand with incremental                                                                         (b) Capacity lags demand with incremental
                                   expansion                                                                                                   expansion

                                                 New                                                                                                          New
                                               capacity                                                                                                     capacity

                                                                                                                                                                                                                   Expected
                            Demand




                                                                                                                                             Demand




                                                                                   Expected                                                                                                                        demand
                                                                                   demand




                                                       1          2       3                                                                                           1        2       3
                                                             Time (years)                                                                                                 Time (years)
                                                                                         Figure S7.6                                                                                                                     Figure S7.6
© 2011 Pearson Education, Inc. publishing as Prentice Hall                                             S7 - 53   © 2011 Pearson Education, Inc. publishing as Prentice Hall                                                            S7 - 54




                                                                                                                                                                                                                                                 9
10/16/2010




                        Reducing Risk with                                                                                   Expected Monetary Value
                       Incremental Changes                                                                                 (EMV) and Capacity Decisions
                        (c) Attempts to have an average capacity
                            with incremental expansion
                                                                                                                                                 Determine states of nature
                                              New
                                            capacity                                                                                                         Future demand
                                                                                    Expected
                                                                                                                                                             Market favorability
                            Demand




                                                                                    demand
                                                                                                                                                 Analyzed using decision trees
                                                                                                                                                             Hospital supply company
                                                                                                                                                             Four alternatives
                                                    1             2       3
                                                             Time (years)
                                                                                               Figure S7.6
© 2011 Pearson Education, Inc. publishing as Prentice Hall                                                   S7 - 55   © 2011 Pearson Education, Inc. publishing as Prentice Hall                                        S7 - 56




      Expected Monetary Value                                                                                                Expected Monetary Value
    (EMV) and Capacity Decisions                                                                                           (EMV) and Capacity Decisions
                                                                     Market favorable (.4)                                                                                          Market favorable (.4)
                                                                                               $100,000                                                                                                       $100,000

                                                                     Market unfavorable (.6)                                                                                        Market unfavorable (.6)
                                                                                               -$90,000                                                                                                       -$90,000

                                                                     Market favorable ( 4)
                                                                                      (.4)                                                                                          Market favorable ( 4)
                                                                                                                                                                                                     (.4)
                                                                                               $60,000                                                                                                        $60,000
                                     Medium plant                                                                                                      Medium plant
                                                                     Market unfavorable (.6)
                                                                                               -$10,000                                                Large Plant                  Market unfavorable (.6)
                                                                                                                                                                                                              -$10,000


                                                                     Market favorable (.4)
                                                                                                                                          EMV = (.4)($100,000)                      Market favorable (.4)
                                                                                               $40,000                                          + (.6)(-$90,000)                                              $40,000

                                                                     Market unfavorable (.6)                                                                                        Market unfavorable (.6)
                                                                                               -$5,000                                    EMV = -$14,000                                                      -$5,000

                                                                                               $0                                                                                                             $0

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      Expected Monetary Value
    (EMV) and Capacity Decisions                                                                                                 Strategy-
                                                                                                                                 Strategy-Driven Investment
                                                        -$14,000
                                                                     Market favorable (.4)
                                                                                               $100,000

                                                                     Market unfavorable (.6)
                                                                                               -$90,000
                                                                                                                                             Operations may be responsible
                                                         $18,000                                                                             for return-on-investment (ROI)
                                                                     Market favorable ( 4)
                                                                                      (.4)
                                     Medium plant
                                                                                               $60,000
                                                                                                                                             Analyzing capacity alternatives
                                                                     Market unfavorable (.6)
                                                                                               -$10,000                                      should include capital
                                                         $13,000
                                                                     Market favorable (.4)
                                                                                                                                             investment, variable cost, cash
                                                                                               $40,000
                                                                                                                                             flows, and net present value
                                                                     Market unfavorable (.6)
                                                                                               -$5,000

                                                                                               $0

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                                                                                                                                                                                                                                   10
10/16/2010




                 Net Present Value (NPV)                                                                                     Net Present Value (NPV)
        In general:                                                                                                 In general:
                                                     F = P(1 +          i)N                                                                                      F = P(1 + i)N
                          where                     F        = future value                                                           where                     F        = future value
                                                    P        = present value
                                                                      t l                                                                                       P                While this works
                                                                                                                                                                         = present value
                                                                                                                                                                                  t l
                                                     i       = interest rate                                                                                     i                     fine, it is
                                                                                                                                                                         = interest rate
                                                    N        = number of years                                                                                  N                cumbersome for
                                                                                                                                                                         = number of years
                                                                                                                                                                               larger values of N
        Solving for P:                                                                                              Solving for P:
                                                                    F                                                                                                          F
                                                      P=                                                                                                          P=
                                                                 (1 + i)N                                                                                                   (1 + i)N
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                            NPV Using Factors                                                                        Present Value of an Annuity
                                                                F
                                              P=
                                                             (1 + i)N
                                                                      = FX                                                       An annuity is an investment which
                                                                                                                                 generates uniform equal payments
                 where                       X = a factor from Table S7.1
                                                 defined as = 1/(1 + i)N and                                                                                             S = RX
                                                 F = future value
                                                                                                                        where                    X = factor from Table S7.2
                                Year             6%            8%        10%      12%      14%                                                   S = present value of a series of
                                 1               .943          .926      .909     .893     .877                                                      uniform annual receipts
     Portion of
     Table S7.1                  2               .890          .857      .826     .797     .769                                                  R = receipts that are received every
                                 3               .840          .794      .751     .712     .675                                                      year of the life of the investment
                                 4               .792          .735      .683     .636     .592
                                 5               .747          .681      .621     .567     .519

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         Present Value of an Annuity                                                                                 Present Value of an Annuity
      Portion of Table S7.2
                                                                                                                                    $7,000 in receipts per for 5 years
                                                                                                                                    Interest rate = 6%
                       Year              6%                8%          10%       12%      14%
                        1               .943              .926         .909      .893     .877
                        2              1.833
                                       1 833             1.783
                                                         1 783        1.736
                                                                      1 736     1.690
                                                                                1 690    1.647
                                                                                         1 647
                                                                                                                                                                             From Table S7.2
                        3              2.676             2.577        2.487     2.402    2.322                                                                               X = 4.212
                        4              3.465             3.312        3.170     3.037    2.914
                        5              4.212             3.993        3.791     3.605    3.433                                                S = RX
                                                                                                                                              S = $7,000(4.212) = $29,484



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                                                                                                                                                                                                               11
10/16/2010




                                             Limitations
           1. Investments with the same NPV may
              have different projected lives and
              salvage values
           2. Investments with the same NPV may
              have different cash flows                                            All rights reserved. No part of this publication may be reproduced, stored in a retrieval
           3. Assumes we know future interest rates                             system, or transmitted, in any form or by any means, electronic, mechanical, photocopying,
                                                                                         recording, or otherwise, without the prior written permission of the publisher.
                                                                                                            Printed in the United States of America.
           4. Payments are not always made at the
              end of a period


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                                                                                                                                                                               12

Heizer om10 ch07_s-capacity

  • 1.
    10/16/2010 Capacity and Constraint Outline S7 Management Capacity Design and Effective Capacity Capacity and Strategy PowerPoint presentation to accompany Heizer and Render Capacity Considerations Operations Management, 10e Principles of Operations Management, 8e Managing Demand PowerPoint slides by Jeff Heyl Demand and Capacity Management in the Service Sector © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 1 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 2 Outline – Continued Outline – Continued Bottleneck Analysis and Theory of Reducing Risk with Incremental Constraints Changes Process Times for Stations, Applying Expected Monetary Systems, and Cycles Value to Capacity Decisions Theory of Constraints Applying Investment Analysis to Bottleneck Management Strategy-Driven Investments Break-Even Analysis Investment, Variable Cost, and Single-Product Case Cash Flow Multiproduct Case Net Present Value © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 3 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 4 Learning Objectives Learning Objectives When you complete this supplement, When you complete this supplement, you should be able to: you should be able to: 1. Define capacity 5. Determine the expected monetary 2. Determine design capacity, effective value of a capacity decision capacity, and utilization 6. Compute net present value 3. Perform bottleneck analysis 4. Compute break-even analysis © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 5 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 6 1
  • 2.
    10/16/2010 Process Strategies Capacity The throughput, or the number of The objective of a process strategy is units a facility can hold, receive, to build a production process that store, or produce in a period of time meets customer requirements and Determines ete es product specifications within cost fixed costs and other managerial constraints Determines if demand will be satisfied Three time horizons © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 7 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 8 Planning Over a Time Design and Effective Horizon Capacity Options for Adjusting Capacity Long-range Add facilities Design capacity is the maximum planning Add long lead time equipment * theoretical output of a system Intermediate- Subcontract Add personnel range Add equipment Build or use inventory Normally expressed as a rate N ll d t planning Add shifts Effective capacity is the capacity a Short-range Schedule jobs firm expects to achieve given current planning * Schedule personnel Allocate machinery operating constraints Modify capacity Use capacity Often lower than design capacity * Difficult to adjust capacity as limited options exist Figure S7.1 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 9 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 10 Utilization and Efficiency Bakery Example Utilization is the percent of design capacity Actual production last week = 148,000 rolls achieved Effective capacity = 175,000 rolls Design capacity = 1,200 rolls per hour Utilization = Actual output/Design capacity p g p y Bakery operates 7 days/week, 3 - 8 hour shifts Efficiency is the percent of effective capacity Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls achieved Efficiency = Actual output/Effective capacity © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 11 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 12 2
  • 3.
    10/16/2010 Bakery Example Bakery Example Actual production last week = 148,000 rolls Actual production last week = 148,000 rolls Effective capacity = 175,000 rolls Effective capacity = 175,000 rolls Design capacity = 1,200 rolls per hour Design capacity = 1,200 rolls per hour Bakery operates 7 days/week, 3 - 8 hour shifts Bakery operates 7 days/week, 3 - 8 hour shifts Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls Utilization = 148,000/201,600 = 73.4% © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 13 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 14 Bakery Example Bakery Example Actual production last week = 148,000 rolls Actual production last week = 148,000 rolls Effective capacity = 175,000 rolls Effective capacity = 175,000 rolls Design capacity = 1,200 rolls per hour Design capacity = 1,200 rolls per hour Bakery operates 7 days/week, 3 - 8 hour shifts Bakery operates 7 days/week, 3 - 8 hour shifts Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls Utilization = 148,000/201,600 = 73.4% Utilization = 148,000/201,600 = 73.4% Efficiency = 148,000/175,000 = 84.6% © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 15 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 16 Bakery Example Bakery Example Actual production last week = 148,000 rolls Actual production last week = 148,000 rolls Effective capacity = 175,000 rolls Effective capacity = 175,000 rolls Design capacity = 1,200 rolls per hour Design capacity = 1,200 rolls per hour Bakery operates 7 days/week, 3 - 8 hour shifts Bakery operates 7 days/week, 3 - 8 hour shifts Efficiency = 84.6% Effi i 84 6% Efficiency of new line = 75% Design capacity = (7 x 3 x 8) x (1,200) = 201,600 rolls Expected Output = (Effective Capacity)(Efficiency) Utilization = 148,000/201,600 = 73.4% = (175,000)(.75) = 131,250 rolls Efficiency = 148,000/175,000 = 84.6% © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 17 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 18 3
  • 4.
    10/16/2010 Bakery Example Capacity and Strategy Actual production last week = 148,000 rolls Capacity decisions impact all 10 Effective capacity = 175,000 rolls Design capacity = 1,200 rolls per hour decisions of operations Bakery operates 7 days/week, 3 - 8 hour shifts management as well as other Efficiency = 84.6% Effi i 84 6% functional areas of the organization f ti l f th i ti Efficiency of new line = 75% Capacity decisions must be Expected Output = (Effective Capacity)(Efficiency) integrated into the organization’s = (175,000)(.75) = 131,250 rolls mission and strategy © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 19 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 20 Capacity Considerations Economies and Diseconomies of Scale 1. Forecast demand accurately (dollars per room per night) 2. Understand the technology and Average uni cost capacity increments p y 25 - room 75 - room it roadside motel roadside motel m 50 - room 3. Find the optimum roadside motel operating level (volume) Economies Diseconomies 4. Build for change of scale of scale 25 50 75 Number of Rooms Figure S7.2 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 21 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 22 Managing Demand Complementary Demand Demand exceeds capacity Patterns Curtail demand by raising prices, scheduling longer lead time Long term solution is to increase capacity 4,000 – Sales in units Capacity exceeds demand 3,000 – Stimulate market 2,000 – Product changes Jet ski 1,000 – engine Adjusting to seasonal demands sales Produce products with complementary JFMAMJJASONDJFMAMJJASONDJ demand patterns Time (months) Figure S7.3 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 23 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 24 4
  • 5.
    10/16/2010 Complementary Demand Complementary Demand Patterns Patterns Combining both demand patterns reduces the variation 4,000 – 4,000 – Sales in units Sales in units Snowmobile S bil Snowmobile S bil 3,000 – motor sales 3,000 – motor sales 2,000 – 2,000 – 1,000 – Jet ski 1,000 – Jet ski engine engine sales sales JFMAMJJASONDJFMAMJJASONDJ JFMAMJJASONDJFMAMJJASONDJ Time (months) Time (months) Figure S7.3 Figure S7.3 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 25 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 26 Tactics for Matching Demand and Capacity Capacity to Demand Management in the 1. Making staffing changes Service Sector 2. Adjusting equipment Demand management Purchasing additional machinery Appointment, reservations, FCFS rule Selling or leasing out existing equipment 3. Improving processes to increase throughput Capacity 4. Redesigning products to facilitate more management throughput Full time, 5. Adding process flexibility to meet changing temporary, product preferences part-time 6. Closing facilities staff © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 27 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 28 Bottleneck Analysis and Process Times for Stations, Theory of Constraints Systems, and Cycles Each work area can have its own unique The process time of a station is the capacity time to produce a unit at that single Capacity analysis determines the workstation throughput capacity of workstations in a The process time of a system is the system time of the longest process in the A bottleneck is a limiting factor or system … the bottleneck constraint The process cycle time is the time it A bottleneck has the lowest effective takes for a product to go through the capacity in a system production process with no waiting © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 29 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 30 5
  • 6.
    10/16/2010 Process Times for Stations, A Three-Station Three- Systems, and Cycles Assembly Line The system process time is the QuickTime™ and a decompressor are needed to see this picture. process time of the bottleneck after dividing by the number of parallel operations The system capacity is the inverse A B C of the system process time 2 min/unit 4 min/unit 3 min/unit The process cycle time is the total time through the longest path in the Figure S7.4 system © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 31 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 32 Capacity Bread Fill Toast Capacity Analysis Analysis Order 30 sec 15 sec 20 sec 40 sec Wrap 37.5 sec Bread Fill Toast 15 sec 20 sec 40 sec Two identical sandwich lines Toast work station has the longest processing Lines have two workers and three operations time – 40 seconds All completed sandwiches are wrapped The two lines each deliver a sandwich every 40 seconds so the process time of the combined p lines is 40/2 = 20 seconds Bread Fill Toast At 37.5 seconds, wrapping and delivery has the Order 15 sec/sandwich 20 sec/sandwich 40 sec/sandwich Wrap longest processing time and is the bottleneck 30 sec/sandwich 37.5 sec/sandwich Capacity per hour is 3,600 seconds/37.5 Bread Fill Toast seconds/sandwich = 96 sandwiches per hour 15 sec/sandwich 20 sec/sandwich 40 sec/sandwich Process cycle time is 30 + 15 + 20 + 40 + 37.5 = 142.5 seconds © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 33 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 34 Capacity Cleaning Capacity Analysis Analysis Check in 2 min/unit Takes X-ray 2 min/unit Develops X-ray 4 min/unit 24 min/unit X-ray exam Dentist 8 min/unit Check out 6 min/unit 5 min/unit Standard process for cleaning teeth All possible paths must be compared Cleaning and examining X-rays can happen simultaneously Cleaning path is 2 + 2 + 4 + 24 + 8 + 6 = 46 minutes X-ray exam path is 2 + 2 + 4 + 5 + 8 + 6 = 27 Cleaning minutes Takes Develops 24 min/unit Check Longest path involves the hygienist cleaning the Check in Dentist X-ray X-ray out teeth 2 min/unit 2 min/unit 4 min/unit X-ray 8 min/unit 6 min/unit Bottleneck is the hygienist at 24 minutes exam Hourly capacity is 60/24 = 2.5 patients 5 min/unit Patient should be complete in 46 minutes © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 35 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 36 6
  • 7.
    10/16/2010 Theory of Constraints Bottleneck Management Five-step process for recognizing and 1. Release work orders to the system at the managing limitations pace of set by the bottleneck Step 1: Identify the constraint 2. Lost time at the bottleneck represents Step 2: Develop a plan for overcoming the p p p g y lost time for the whole system constraints 3. Increasing the capacity of a non- Step 3: Focus resources on accomplishing Step 2 bottleneck station is a mirage Step 4: Reduce the effects of constraints by 4. Increasing the capacity of a bottleneck offloading work or expanding capability increases the capacity of the whole Step 5: Once overcome, go back to Step 1 and find system new constraints © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 37 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 38 Break- Break-Even Analysis Break- Break-Even Analysis Fixed costs are costs that continue Technique for evaluating process even if no units are produced and equipment alternatives Depreciation, taxes, debt, mortgage Objective is to find the point in payments dollars and units at which cost Variable costs are costs that vary equals revenue with the volume of units produced Requires estimation of fixed costs, Labor, materials, portion of utilities variable costs, and revenue Contribution is the difference between selling price and variable cost © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 39 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 40 Break- Break-Even Analysis Break- Break-Even Analysis – Assumptions 900 – Total revenue line Costs and revenue are linear 800 – Break-even point Total cost line functions 700 – Total cost = Total revenue Cost in dollars 600 – Generally not the case in the y d 500 – real world 400 – Variable cost We actually know these costs 300 – Very difficult to verify 200 – 100 – Fixed cost Time value of money is often – | | | | | | | | | | | | ignored 0 100 200 300 400 500 600 700 800 900 1000 1100 Figure S7.5 Volume (units per period) © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 41 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 42 7
  • 8.
    10/16/2010 Break- Break-Even Analysis Break- Break-Even Analysis BEPx = break-even point in x = number of units BEPx = break-even point in x = number of units units produced units produced BEP$ = break-even point in TR = total revenue = Px BEP$ = break-even point in TR = total revenue = Px dollars F = fixed costs dollars F = fixed costs P = price per unit (after V = variable cost per unit P = price per unit (after V = variable cost per unit all discounts) TC = total costs = F + Vx all discounts) TC = total costs = F + Vx BEP$ = BEPx P Break- Break-even point occurs when = F P Profit = TR - TC P-V = Px - (F + Vx) TR = TC F F or BEPx = = = Px - F - Vx P-V (P - V)/P Px = F + Vx F = (P - V)x - F = 1 - V/P © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 43 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 44 Break- Break-Even Example Break- Break-Even Example Fixed costs = $10,000 Material = $.75/unit Fixed costs = $10,000 Material = $.75/unit Direct labor = $1.50/unit Selling price = $4.00 per unit Direct labor = $1.50/unit Selling price = $4.00 per unit F $10,000 F $10,000 BEP$ = = BEP$ = = 1 - (V/P) 1 - [(1.50 + .75)/(4.00)] 1 - (V/P) 1 - [(1.50 + .75)/(4.00)] $10,000 = = $22,857.14 .4375 F $10,000 BEPx = = = 5,714 P-V 4.00 - (1.50 + .75) © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 45 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 46 Break- Break-Even Example Break- Break-Even Example 50,000 – Multiproduct Case Revenue 40,000 – F Break-even BEP$ = point 30,000 – Total ∑ 1- Vi x (Wi) Dollars s costs t Pi 20,000 – Fixed costs where V = variable cost per unit 10,000 – P = price per unit F = fixed costs – | | | | | | W = percent each product is of total dollar sales 0 2,000 4,000 6,000 8,000 10,000 Units i = each product © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 47 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 48 8
  • 9.
    10/16/2010 Multiproduct Example Multiproduct Example Fixed costs = $3,000 per month Fixed costs = $3,000 per month Annual Forecasted Annual Forecasted Item Price Cost Sales Units Item Price Cost Sales Units Sandwich $5.00 $3.00 9,000 Sandwich $5.00 $3.00 9,000 Drink 1.50 .50 9,000 Drink 1.50 .50 9,000 Baked potato 2.00 2 00 1.00 1 00 7,000 7 000 Baked potato 2.00 2 00 1.00 1 00 7,000 7 000 Annual Weighted Selling Variable Forecasted % of Contribution Item (i) Price (P) Cost (V) (V/P) 1 - (V/P) Sales $ Sales (col 5 x col 7) Sandwich $5.00 $3.00 .60 .40 $45,000 .621 .248 Drinks 1.50 .50 .33 .67 13,500 .186 .125 Baked 2.00 1.00 .50 .50 14,000 .193 .096 potato $72,500 1.000 .469 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 49 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 50 Multiproduct Example F Reducing Risk with BEP = ∑ 1 - P x (W ) V $ i i Incremental Changes Fixed costs = $3,000 per month i (a) Leading demand with (b) Capacity lags demand with incremental expansion incremental expansion $3,000 x Forecasted Annual 12 New Item Price Cost = Sales Units = $76,759 New .469 capacity capacity Demand Sandwich $5.00 $3.00 9,000 Demand Expected Expected demand demand Drink 1.50 .50 Daily 9,000 $76,759 Baked potato 2.00 2 00 1sales = 312 days = $246.02 1.00 00 7 000 $246 02 7,000 Annual Weighted Selling Variable .621 x $246.02 of Contribution Forecasted % (c) Attempts to have an average Item (i) Price (P) Cost (V) (V/P) 1 - (V/P) Sales $ = 30.6 ≈ 31 Sales (col 5 x col 7) capacity with incremental $5.00 sandwiches expansion Sandwich $5.00 $3.00 .60 .40 $45,000 .621 per day .248 New Drinks 1.50 .50 .33 .67 13,500 .186 .125 Demand capacity Expected Baked 2.00 1.00 .50 .50 14,000 .193 .096 demand potato $72,500 1.000 .469 Figure S7.6 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 51 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 52 Reducing Risk with Reducing Risk with Incremental Changes Incremental Changes (a) Leading demand with incremental (b) Capacity lags demand with incremental expansion expansion New New capacity capacity Expected Demand Demand Expected demand demand 1 2 3 1 2 3 Time (years) Time (years) Figure S7.6 Figure S7.6 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 53 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 54 9
  • 10.
    10/16/2010 Reducing Risk with Expected Monetary Value Incremental Changes (EMV) and Capacity Decisions (c) Attempts to have an average capacity with incremental expansion Determine states of nature New capacity Future demand Expected Market favorability Demand demand Analyzed using decision trees Hospital supply company Four alternatives 1 2 3 Time (years) Figure S7.6 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 55 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 56 Expected Monetary Value Expected Monetary Value (EMV) and Capacity Decisions (EMV) and Capacity Decisions Market favorable (.4) Market favorable (.4) $100,000 $100,000 Market unfavorable (.6) Market unfavorable (.6) -$90,000 -$90,000 Market favorable ( 4) (.4) Market favorable ( 4) (.4) $60,000 $60,000 Medium plant Medium plant Market unfavorable (.6) -$10,000 Large Plant Market unfavorable (.6) -$10,000 Market favorable (.4) EMV = (.4)($100,000) Market favorable (.4) $40,000 + (.6)(-$90,000) $40,000 Market unfavorable (.6) Market unfavorable (.6) -$5,000 EMV = -$14,000 -$5,000 $0 $0 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 57 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 58 Expected Monetary Value (EMV) and Capacity Decisions Strategy- Strategy-Driven Investment -$14,000 Market favorable (.4) $100,000 Market unfavorable (.6) -$90,000 Operations may be responsible $18,000 for return-on-investment (ROI) Market favorable ( 4) (.4) Medium plant $60,000 Analyzing capacity alternatives Market unfavorable (.6) -$10,000 should include capital $13,000 Market favorable (.4) investment, variable cost, cash $40,000 flows, and net present value Market unfavorable (.6) -$5,000 $0 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 59 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 60 10
  • 11.
    10/16/2010 Net Present Value (NPV) Net Present Value (NPV) In general: In general: F = P(1 + i)N F = P(1 + i)N where F = future value where F = future value P = present value t l P While this works = present value t l i = interest rate i fine, it is = interest rate N = number of years N cumbersome for = number of years larger values of N Solving for P: Solving for P: F F P= P= (1 + i)N (1 + i)N © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 61 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 62 NPV Using Factors Present Value of an Annuity F P= (1 + i)N = FX An annuity is an investment which generates uniform equal payments where X = a factor from Table S7.1 defined as = 1/(1 + i)N and S = RX F = future value where X = factor from Table S7.2 Year 6% 8% 10% 12% 14% S = present value of a series of 1 .943 .926 .909 .893 .877 uniform annual receipts Portion of Table S7.1 2 .890 .857 .826 .797 .769 R = receipts that are received every 3 .840 .794 .751 .712 .675 year of the life of the investment 4 .792 .735 .683 .636 .592 5 .747 .681 .621 .567 .519 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 63 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 64 Present Value of an Annuity Present Value of an Annuity Portion of Table S7.2 $7,000 in receipts per for 5 years Interest rate = 6% Year 6% 8% 10% 12% 14% 1 .943 .926 .909 .893 .877 2 1.833 1 833 1.783 1 783 1.736 1 736 1.690 1 690 1.647 1 647 From Table S7.2 3 2.676 2.577 2.487 2.402 2.322 X = 4.212 4 3.465 3.312 3.170 3.037 2.914 5 4.212 3.993 3.791 3.605 3.433 S = RX S = $7,000(4.212) = $29,484 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 65 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 66 11
  • 12.
    10/16/2010 Limitations 1. Investments with the same NPV may have different projected lives and salvage values 2. Investments with the same NPV may have different cash flows All rights reserved. No part of this publication may be reproduced, stored in a retrieval 3. Assumes we know future interest rates system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Printed in the United States of America. 4. Payments are not always made at the end of a period © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 67 © 2011 Pearson Education, Inc. publishing as Prentice Hall S7 - 68 12