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  • Presentation Abstract: Estimation, planning and control processes can make the difference between project success and project failure. Unfortunately, estimation is often considered unimportant by the engineering community, who may just want to make the best, fastest, etc. without considering affordability. This paper covers estimation best practices, estimation process maturity, and examples of estimation, planning and control done right. Estimation process maturity -- what it is, how to apply it to your programs and how to seek the appropriate level for your organization -- will be discussed, along with the Return on Investment of such practices.Presentation Synopsis: Estimation, planning and control processes decide project success. This paper covers estimation best practices, process maturity, and examples. Estimation process maturity -- definintion, application, and how to seek the appropriate level for your organization -- will be discussed, along with the Return on Investment of such practices.
  • Estimation, planning and control processes can make the difference between project success and project failure. Unfortunately, estimation is often considered unimportant by the engineering community, who may just want to make the best, fastest, etc. without considering affordability. This paper covers estimation best practices, estimation process maturity, and examples of estimation, planning and control done right.  Estimation process maturity -- what it is, how to apply it to your programs and how to seek the appropriate level for your organization -- will be discussed, along with the Return on Investment of such practices. 
  • University of Toronto Department of Computer Science© 2001, Steve EasterbrookAriane-5 Events➜ Locus of error:Platform alignment software (part of the Inertial Reference System, SRI)This software only produces meaningful results prior to launchStill operational for 40 seconds after launch➜ Cause of error:Ada exception raised and not handled:Converting 64-bit floating point to 16-bit signed integer for Horizontal Bias (BH)Requirements state that computer should shut down if unhandled exception occurs➜ Launch+30s: Inertial Reference Systems failBackup SRI shuts down firstActive SRI shuts down 50ms later for same reason➜ Launch+31s: On-board Computer receives data from active SRIDiagnostic bit pattern interpreted as flight dataOBC commands full nozzle deflectionsRocket veers off course➜ Launch+33s: Launcher starts to disintegrateSelf-destruct triggered12University of Toronto Department of Computer Science© 2001, Steve EasterbrookWhy did this failure occur?➜ Why was Platform Alignmentstill active after launch?SRI Software reused from Ariane-440 sec delay introduced in case of ahold between -9s and -5sSaves having to reset everythingFeature used once in 1989➜ Why was there no exceptionhandler?An attempt to reduce processorworkload to below 80%Analysis for Ariane-4 indicatedoverflow was not physically possibleAriane-5 had a different trajectory➜ Why wasn’t the designmodified for Ariane-5?Not considered wise to change softwarethat worked well on Ariane-4➜ Why did the SRIs shut down?Assumed faults are random hardwarefailures, hence should switch to backup➜ Why was the error not caughtin unit testing?No trajectory data for Ariane-5 wasprovided in the requirements for SRIs➜ Why was the error not caughtin integration testing?Full integration testing considered toodifficult/expensiveSRIs were considered to be fullycertifiedIntegration testing used simulations ofthe SRIs➜ Why was the error not caughtby inspection?The implementation assumptionsweren’t documented➜ Why did the OBC usediagnostic data as flightdata?They assumed this couldn’t happen
  • Dan galorath

    1. 1. Estimation & Planning Processes DecideProject SuccessNASA Project Management Challenge 2012Dan Galorath, Founder & CEO Copyright Galorath Incorporated 2011
    2. 2. Introduction• Estimating is critical for all kinds of systems • Yet many treat is as a second rate process• Having a repeatable estimation process is critical to both estimating AND to successful projects• Estimation and measurement go hand in hand © 2009 Copyright Galorath Incorporated 2
    3. 3. Delusions of Success: How OptimismUndermines Executives Decisions Richard Hartley, HBR) (Source:• Problem: Humans seem hardwired to be optimists• Optimism from cognitive biases & organizational pressures • Exaggerate talents & degree of control • Attribute negative consequences to external factors• Anchoring (relying too heavily on one piece of information) magnifies optimism Solution: Temper with “outside view” • Most pronounced for new initiatives Supplement traditional forecasting w/ statistical Parametrics Don’t remove optimism, but balance optimism & realism
    4. 4. Example of Tempering: (Source How ToMeasure Anything)• German Mark V Tanks• Allies estimated production by analyzing serial numbers• Used the captured tanks as a random sample and predicted probability of various production levels
    5. 5. An Estimate Defined• An estimate is the most knowledgeable statement you can make at a particular point in time regarding: • Effort / Cost • Schedule • Staffing • Risk • Reliability• Estimates more precise with progress• A WELL FORMED ESTIMATE IS A DISTRIBUTION 5
    6. 6. Estimation Methods 1 of 2 Model Description Advantages Limitations Category No Basis or substantiationGuessing Quick Can obtain any No Process Off the cuff estimates(Common) answer desired Usually Wrong Generally optimistic Truly similar projects mustAnalogy Compare project with past Estimates are based on exist.(Common) similar projects. actual experience. Less optimistic Experts tend to be biased;Expert Little or no historical knowledge level is sometimes Consult with one or moreJudgment data is needed; good for questionable; may not be experts.(Common) new or unique projects. consistent. Generally optimistic A hierarchical Need valid requirements. Provides an estimate decomposition of the Difficult to track architecture;Top Down linked to requirements system into progressively engineering bias may lead toEstimation and allows common smaller components is used underestimation.(Common) libraries to size lower to estimate the size of a Generally optimistic (miss level components. software component. non-WBS items) 6
    7. 7. Estimation Methods 2 of 2 Model Category Description Advantages Limitations Uses expert judgment to determine how Easy to get under Design To Cost Little or no engineering basis. much functionality can stakeholder (sometimes) Optimistic be provided for given number budget. Simple relationships may not tell the Equation with one or whole story Simple CER’s more unknowns that Some basis in Historical data may not tell the whole (common) provides cost / data story schedule estimate Less optimistic Models are usually fast and Models can be inaccurate if not easy to use, and properly calibrated and validated; Perform overall useful early in a historical data may not be relevant Comprehensive estimate using design program; they are to new programs; optimism in Parametric Models parameters and also objective parameters may lead to (common) mathematical and repeatable. underestimation. algorithms. Easy tradeoffs More or less optimistic depending can provide on parameters better plansWhy should we care: Each method has challenges andwe should be familiar with each 7
    8. 8. Common Challenges In Estimating• High effort and expenses in producing estimates Proposals - Acquisition Strategy inputs• Informal request - POM budgets• Significant investment in time to generate numbers• Weak accuracy in numbers leading to cost overruns• Customer frequent request for revisions cause even most expenses• Numbers susceptible to many forces without robust cost generation systems• Lack of understanding of cost risk• Difficulty in calibrating “Engineering Judgment © 2009 Copyright Galorath Incorporated 8
    9. 9. Poor Estimates Effect on Projects• Inaccurate estimates can reduce project success: • Poor implementations • Critical processes don’t scale • Emergency staffing • Cost overruns caused by underestimating project needs• Scope creep • Forever changing project goals • Frustration • Customer dissatisfaction • Cost overruns and missed schedules • Project Failures• Important project business decisions made early with minimum knowledge & maximum uncertaintyWhy should we care: Poor estimates and plans area root cause of program failure 9
    10. 10. Initial Cost Estimation Problems (SoftwareProgram Managers Network)• Many programs that have been evaluated tend to initially estimate using a very optimistic method. • Low bid to win contract • Naïve level of effort estimation • Human optimism (HBR & Rich Hartley USAF Undersec Acquisition) • Often wrong since they are not based on a thorough analysis of requirements. The formula Cost = Size x Complexity/Productivity• Has three unknowns upfront: size, complexity, and productivity.• Methods & estimating tools determine size given system requirements• Organizational databases of productivity on comparable size and complexity projects can be used • Or other bottom-up estimation techniques “In any event, all initial cost estimates should be considered as potential high risk and should be reviewed at each program review” SPMN
    11. 11. Software Is A Critical Component of Military & Aerospace Systems Failures Ariane 5 • Ariane 5 video • Note: $500 Million payload • Failure due to reused software from (Ariane 4) • with incompatible assumptions for exception condition that was not required“the culture within the Ariane program…” only addressed“random hardware failures… which can quite rationally behandled by a backup system”“the view had been taken that software should be consideredcorrect until it is shown to be at fault”! Why should we care: Software cost & schedule should be sufficient for successful missions
    12. 12. Software Is A Key Risk Item InWeapons Systems• Navy Mobile User Objective Satellite Communication System delays to the Joint Tactical Radio System, a set of software-defined radios causes advanced MUOS capabilities to drastically underused… GAO• GAO identified 42 programs at risk for cost & schedule 1. military requirements changes 2. software development challenges 3. workforce issues• National Institute of Standards and Technology (NIST) • Software defects cost nearly $60 Billion Annually • 80% of development costs involve identifying and correcting defectsSoftware, not Hardware or technology readiness levelswere called out
    13. 13. Death March Projects Are Likely To Fail Why should we care: If you have a project on a death march failure is highly probably
    14. 14. Balancing Resources & Schedule IsA Science For a given Size, Complexity and Technology Minimum Time Work Expands To Fill Time To Complete (Effort Increases (Effort Increases due to lack of pressure ) to Reduce Schedule) Effort Increase Minimum Time due to LongerEffort Months Schedule Optimal Effort (Lower Effort for Longer Schedule) Calendar Time
    15. 15. Why Total Cost Grew for Two Space Programs David Graham, NASA Development Growth Causes Requirements Generation & Translation 8% Budget/Funding 11% 25% Cost Estimation Underestimation of Risk 11% 11% Schedule Slips (Govt & Contractor) 9% Price Increases 25% Other Quantitative Framework5 “TheSuccess Triangle of Cost, Schedule, and Performance: A Blueprint for Development of Large-ScaleSystems in an Increasingly Complex Environment” - (Booz|Allen|Hamilton, 2003)
    16. 16. Use Earned Value To Quantify ProgressVersus Effort (Oversimplified)• Main EVM concern is what has been accomplished in a given time and budget, versus what was planned for the same time and budget • Project generally deemed healthy if what has been accomplished is what was planned, or more • Project deemed unhealthy if accomplishment lags expectations• Definition: Earned value = budgeted value for the work accomplished (what you got for what it cost you) Healthy Unhealthy $ Budget $ Budget EV EV Time = Now Time = Now 16
    17. 17. Deploying Before Complete Leads To ProgramDisasters: You Better Understand Schedule 17
    18. 18. Understand Project Risks Include Them In PlanningDecisions (Example SEER-SEM Outputs)Probability Schedule Probability Probability Effort Probability Example Application 1 Example Application 1 99% 99% 90% 90% 80% 80% 70% 70% 60% 60% 50% 50% 40% 40% 30% 30% 20% 20% 10% 10% 1% 1% 0 4 8 12 16 20 0 1800 3600 5400 7200 9000 Time (calendar months) Effort (person-hours) Defects Probability Probability Example Application 1 99% 90% 80% 70% 60% 50% 40% 30% 20% 10% 1% 0 12 24 36 48 60 Defects (count) 18
    19. 19. Considering Maintenance During Planning CanYield More Successful Long Term Results Staff Vs Maintenance Rigor 3500 staff hours per month 3000 2500 develop 2000 Rigor vhi+ 1500 Rigor nom 1000 Rigor vlo 500 0 1 7 13 19 25 31 37 43 49 55 61 67 73 79 85 Time 19
    20. 20. Data Doesn’t Have To Be Perfect To BeUseful: But Is Has To Be Viable• 80 Calories per serving• 2.5 Servings per can• 4 Ounces, Condensed, 8 Ounces With Water
    21. 21. You have an estimate …Now what? 21
    22. 22. The Error of Causal AnalysisCreating a False Association• Correlation does not imply causation • Just because two data points may sit side by side doesn’t mean they are the same or will have the same outcome• Casual analysis is a recognized error in medicine Tumor Can Cause Headache Perhaps ??? Headache doesn’t mean a tumor 22
    23. 23. Use Historical Measurement toevaluate your estimate! It’s easy to dig deeper and deeper to justify an estimate! 23
    24. 24. Data Beware Apples and Oranges:Phase : All activities may not be included. System Concept Integration missing missing Phases System Concepts System Req & Design System Req Analysis Preliminary Design Detailed Design Code / Unit Testing Software Test System Integration / OT&E 24
    25. 25. Estimation Process 25
    26. 26. Basic Cost Estimating Process (Source CEBOK) WBS • Work Breakdown Structure (WBS) Development Baseline • Program/System Baseline Data Collection Development Data AnalysisMethodology Validation Reports 26
    27. 27. US GAO process for CredibleEstimates 27
    28. 28. 10 Step System Estimation Process 20111. Establish Estimate Scope 10. Track Project Throughout Development2. Establish Technical 9. Document Estimates Baseline, Ground and Lessons Rules, Assumptions Learned 8. Generate a Project Plan 4. Refine Technical Baseline Into Estimable Components 6. Validate Business Case Costs & Benefits (go / no go) 4. Collect data / estimation inputs 6. Quantify Risks and Risk Analysis 5. Estimate Baseline Cost, Schedule, Affordability Value 28
    29. 29. Estimation Organizational Maturity V1.7 Level Informal or no Manual effort estimating 0 estimating without a process Level Direct Task Spreadsheets Ad Hoc 1 Estimation Process Formal Simple model Level Sizing (e.g. Direct Task (Size * Productivity) or informal Some measureme Informal 2 Process nt & function Estimation SEER Use analysis points) Level Formal Robust Parametric Estimate vs. Formalized Multiple Rigorous measurement Parametric planning & Risk Repeatable 3 Sizing estimation actual capture Estimate Management process & analysis Control (SEER) Process Level Formal sizing Repeatable Robust parametric Rigorous measurement Parametric estimation Risk Process improvement 4 process estimating with tracking Management via lessons & analysis (SEER) & control learned Level Formal sizing Repeatable Robust parametric Rigorous measurement Parametric estimation Risk Continuous process 5 process estimating with tracking Management & analysis improvement (SEER) & controlWhy should we care? Maturity is related to estimateviability… With better estimation process, projectsmore likely to be successful in execution
    30. 30. Estimation Should Be Key Part of Process (Source Q Redman, APMP Just Say No) Phase -1 0 1 2 3 4 DDE ROM ROM Formal Bid Gate 4Scope & Accuracy ROM 15-20 people ROM 4 weeks (Bid Stds+ History) EARLY ESTIMATING Modified 3-5 people, 3 - 5 days Budgetary Top Down, parametric model Estimate based price estimating Draft RFP/Gate 3 Vs. 6-8 people, 3 Current state: 90 people, 6wks weeks (Bid Stds + History ) Market Opportunity Acquisition Us Creation/ Customer Procurement e Assessment/ Planning/ POM Draft RFP RFP Decision Plans Initiation “What If’s” and Plus Ups 30
    31. 31. GAO Publication: Characteristics of credible costestimates and a reliable process for creating them• This chapter discusses a 1972 GAO report on cost estimating • We reported that cost estimates were understated and causing unexpected cost growth • Many of the factors causing this problem are still relevant today• We also discuss a 12 step process for producing high quality cost estimates 31
    32. 32. GAO Publication: Why cost estimates are requiredfor government programs and challenges developingcredible results• Introduces why cost estimates are required for government programs • Developing annual budgets, supporting management decisions about which program to fund, and evaluating resource requirements at key decision points• Discusses various challenges associated with developing credible results 32
    33. 33. Ask These Questions WhenIdentifying Estimate Scope• Challenged projects • Would you still go forward if you knew • Schedule would be significantly longer? • Cost would be dramatically higher? • Probably: but perhaps more insight could identify mitigation • Plan functionality differently • Certainly you could notify stakeholders of real costs • Ensure staffing is appropriate for the constraints• Failed Projects • Would you start a project you knew was unaffordable? Or if schedule was completely unrealistic? • If knowing up-front could you do something about it? • Often better to kill project before it begins than waste resources & let the organization down 33
    34. 34. Lesson Learned: Estimate MustQuantify Risk & Uncertainty Firm Fixed Price? Feel lucky? What is likely to happen Understand the risk before you commit! 34 34
    35. 35. Estimation Best Practices © 2011 Copyright Galorath Incorporated
    36. 36. Cost Estimate Qualities(Adapted from CEBOK)• The characteristics of high quality cost estimates are: • Accurate (Viable Within Range) • Comprehensive • Replicable and Auditable • Traceable • Credible • Timely 36 Unit I - Module 1
    37. 37. System Description (Parametrics CanEstimate More, Earlier) Adapted from CEBOK “If you can’t tell me what it is, I can’t tell you what it costs.” -Mike Jeffers “If you can tell me the range of what it might be I can tell you the range of cost, schedule & probability” -Dan Galorath 37
    38. 38. Types of Cost Estimates (Adapted FromCEBOK)• Life Cycle Cost Estimate (LCCE)• Independent Cost Estimate (ICE) 1• Budget Estimate• Rough Order of Magnitude (ROM)• Estimate At Completion (EAC)• Independent Cost Assessment (ICA)• Analysis of Alternatives (AoA)• Economic Analysis (EA) 38 Unit I - Module 1
    39. 39. Aircraft Example: Estimating Techniques Adapted from CEBOK)• Where applicable, use primary methods• Analogy • Model X100 series jet engines have only been used on one other plane, but weight is 100% higher on this model; estimate 2x other model• Simple Parametric Param etric Estim ate • As shown, need to estimate 2 lb 12 brake rotors, should be roughly $4M 10 from regression curve 8 Cost 6• Commercial Parametric 4 2 • Key characteristics range are 0 0 2 4 6 8 10 Param eter (ie. w eight) • 30-50k lines of code and 600-800 • kilos engine & 7 PC boards• Engineering Build-Up • Know Air Conditioning (AC) system costs on plane because received quotes from HVAC vendor for all duct work and AC blower off the 39 shelf
    40. 40. Manual Estimates: Human Reasons ForError (Metrics Can Help)• Manual Task estimates yield SIGNIFICANT error• Desire for “credibility” motivates overestimate behavior (80% probability?) • So must spend all the time to be “reliable” • Better approach: force 50% probability & have “buffer” for overruns• Technical pride sometimes causes underestimates 40
    41. 41. Lesson Learned: The Risk In Risk Analysis "Its tough to make predictions, especially about the future." -- Yogi Berra.41
    42. 42. Cost Readiness Levels at Low TRLs and/or Less Than Firm Requirements• If the project has critical items at less than TRL 4… • Like asking Edison in 1876 “How much longer for the light bulb” • “Hard to say”, he would have said as he had you thrown out • Note that this is not the same as asking, in 1879, once he had found a workable carbon filament, “How TRL 9 TRL9: Actual system “flight proven” thorough successful mission operations much will a production version of TRL 8 TRL8: Actual system completed and “flight qualified” through test and demonstration the light bulb cost to develop and TRL 7 TRL7: System prototype demonstration in a space environment produce Tom?” TRL 6 TRL6: System/subsystem model or prototype demonstration in a relevant environment TRL • This would have been a TRL 4 5 TRL5: Component and/or breadboard validation in relevant environment TRL question 4 TRL4: Component and/or breadboard validation in laboratory environment TRL • Tom’s cost estimators could have 3 TRL TRL3: Analytical and experimental critical function and/or characteristic proof-of-concept begun to model this 2 TRL TRL2: Technology concept and/or application formulated TRL1: Basic principles observed and reported• 1 So if 1<TRL<3 CRL < 4• Likewise, if requirements are not firm,  CRL < 4 42
    43. 43. Table 1: CRL Rating Prior to Availability of Probabilistic Risk Analysis Basic CRL9 5 5.5 6 6.5 7 7.5 8 8.5 9“Complexity*” CRL Description of the CRL8 4.5 5 5.5 6 6.5 7 7.5 8 8.5 to go work at the time CRL7 End of project actual cost of the 4 4.5 5 5.5 6 6.5 7 7.5 8 9 estimate CRL6 3.5 4 4.5 5 5.5 6 6.5 7 7.5 Cost fit for very firm 8 engineering decisions and very firm budget commitments (+/-5%) CRL5 3 3.5 4 4.5 5 5.5 6 6.5 7 Cost fit for firm CRL4 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 engineering decisions and firm budget commitments (+/-15%) CRL3 2 2.5 3 3.5 4 4.5 5 5.5 6 Cost fit for PDR CRL2 6 engineering decisions and 1.5 2 2.5 3 3.5 4 4.5 5 5.5 PDR budget use (+/-25%) CRL1 1 1.5 2 2.5 3 3.5 4 4.5 5 Cost fit for preliminary 5 engineering decisions and Extrem Very Very Very Very Very Very Very Very preliminary budget use (+/- el 35%) Minimal Cost fit for very 4 preliminary engineering decisions and very *Complexity considerations include human rating, launch Adequacy of “Estimating Methods”, preliminary budget use (+/- system requirements, planetary destination, operational vs experimental requirements, materials complexity, use of experience of the estimators, quality of 45%) deployables, parts count, challenging thermal CARD, availability of analogous data and requirements, high data rates, electronic parts cost tools, time allowed for estimate, class, stabilization requirements, power generation independence of estimate, number of 43 type, propellant choice, propulsion requirements and many other factors. Programmatic complexity includes team cross checks performed size, team experience, schedule and many other factors.
    44. 44. Table 2: CRL Rating After Availability of Probabilistic Risk Analysis Use S Curve inter-quartile cost range to translate to a CRL rating –Calculate ratio of 75th percentile cost to 25th percentile cost; then lookup ratio on chart to read CRL Lookup25th Percentile Median Cost 75th Percentile Cost Ratio of 75th Read Cost Percentile Cost to 25th CRL Percentile Cost Description End of project actual cost 100 100 100 1.00 9 Cost fit for very firm 95 100 105 1.11 8 engineering decisions and very firm budget commitments (+/-5%) Cost fit for firm engineering 85 100 115 1.35 7 decisions and firm budget commitments (+/-15%) Cost fit for PDR engineering 75 100 125 1.67 6 decisions and PDR budget use (+/-25%) Cost fit for preliminary 65 100 135 2.08 5 engineering decisions and preliminary budget use (+/-35%) Cost fit for very preliminary 55 100 145 2.64 4 engineering decisions and very 44 preliminary budget use (+/-45%)
    45. 45. Estimation Best Practices• Decide Why You Want An Estimate• Map Estimation Goals To Estimate Process Maturity & Develop Plan To Achieve The Maturity• Have A Documented, Repeatable Estimation Process• Make The Estimating Process As Simple As Possible; But No Simpler• Be Proactive: The Process Is Important, The Tools Go Along With The Process• Get Buy-in From Program Managers• Hold People Accountable: Center Of Excellence Can Prepare Estimate But Program Managers Must Own Them• Tie The Estimate To The Plan 45
    46. 46. Estimation Best Practices 2• Evaluate Total Ownership Cost; Not Just Development• Estimate A Range And Pick A Point For The Plan• Re-estimate The Program When It Changes• Avoid Death Marches: Programs With Unachievable Schedules Are Likely To Fail And Drain Morale• Keep A History: Start An Enterprise Database NOW…• Business Case: Evaluate ROI In Addition To Costs• Convert Expert Spreadsheets Into A Common Language 46
    47. 47. Estimation Best Practices 3• Track Progress Vs. Estimate Throughout The Life Cycle• Estimate Schedule As Well As Effort (Cost) For Complete Picture• Tie The Business Case Into The Estimating Process• Attack Non-productive Rework As Part Of The Process 47
    48. 48. Estimation Best Practices 4• Have clear definitions: • What does “complete” mean • What activities are included and excluded (E.g. development only or total ownership; help desk included or excluded, etc.) • Which labor categories are included and excluded in the estimate (e.g. are managers included? Help desk? Etc.)• Don’t ignore IT infrastructure and IT services costs• Tracking defect sources can go along with the process 48
    49. 49. Project Management ChallengesRelate To Estimation Planning• “No good deed will go unpunished.” Unreasonable expectations on the next project are supported by heroic behavior on the previous project• The most important business decisions about a software project are made at the time of minimum knowledge and maximum uncertainty.• Adding and/or changing means more time and/or more effort• When a project is in trouble ask for more time rather than more people. Deferring functionality common approach to asking for more time• Increasing concurrency is usually not a solution (e.g. designing several releases concurrently) A1-49
    50. 50. 7 Characteristics of DysfunctionalSoftware Projects (Source: Mike Evans, et al.)• Based on 350 projects: • Failure to Apply Essential Project Management Practices • Unwarranted Optimism and Unrealistic Management Expectations • Failure to Implement Effective Software Processes • Premature Victory Declarations • Lack of Program Management Leadership • Untimely Decision-Making • Lack of Proactive Risk Management 50
    51. 51. Additional Information• www.galorath.com• Dan on estimating BLOG: www.galorath.com/wp• Email: galorath@galorath.com © 2009 Copyright Galorath Incorporated 51