Wesco International provides reconciliations of non-GAAP financial measures for the twelve months ended June 30, 2008 and 2007. EBITDA is calculated as income from operations plus depreciation and amortization. Total debt as of June 30, 2008 is $1.245 billion with a financial leverage ratio of 3.0. Free cash flow is calculated as net income plus depreciation and amortization, less changes in working capital items and capital expenditures, resulting in $37.7 million for the three months ended June 30, 2008. Gross profit is calculated by deducting cost of goods sold excluding depreciation from net sales, resulting in a gross margin of 19.5% for the three months

1. WESCO INTERNATIONAL, INC.
RECONCILIATION OF NON-GAAP FINANCIAL MEASURES
(Unaudited)
Twelve Months Twelve Months
Financial Leverage: Ended Ended
(dollar amounts in thousands) June 30, 2008 June 30, 2007
381,992 379,470
Income from operations $ $
32,268 34,180
Depreciation and amortization
414,260 413,650
EBITDA $ $
Short term debt 500,000 495,500
Current debt 2,730 2,632
Long term debt 742,693 838,485
Total debt $ 1,245,423 $ 1,336,617
3.0 3.2
Financial leverage ratio
Three Months Six Months
Free Cash Flow: Ended Ended
(dollar amounts in millions) June 30, 2008 June 30, 2008
60.1 105.0
Net Income $ $
6.7 13.6
Depreciation and amortization
(53.2) (70.1)
Accounts receivable
(30.8) (3.9)
Inventory
Accounts payable 73.5 96.9
Other (10.3) (3.5)
Cash flow provided by operations $ 46.0 $ 138.0
Less: Capital expenditures (8.3) (19.6)
37.7 118.4
Free cash flow $ $
Note: Free cash flow is provided by the Company as an additional liquidity measure. Capital expenditures
are deducted from operating cash flow to determine free cash flow. This amount represents excess funds
available to management to service all of its financing needs.

2. WESCO INTERNATIONAL, INC.
RECONCILIATION OF NON-GAAP FINANCIAL MEASURES (CONTINUED)
(dollar amounts in millions)
(Unaudited)
Three Months Three Months
Ended Ended
Gross Profit: June 30, 2008 June 30, 2007
1,587.8 1,518.1
Net sales $ $
Cost of goods sold (excluding
1,277.4 1,210.0
depreciation and amortization)
310.4 308.1
Gross profit $ $
19.5% 20.3%
Gross margin
Six Months
Six Months
Ended Ended
June 30, 2008 June 30, 2007
3,053.0 2,968.7
Net sales $ $
Cost of goods sold (excluding
2,447.0 2,361.6
depreciation and amortization)
606.0 607.1
Gross profit $ $
19.8% 20.5%
Gross margin
Note: Gross profit is provided by the Company as an additional financial measure. Gross profit is
calculated by deducting cost of goods sold, excluding depreciation and amortization, from net sales. This
amount represents an important financial measure within the distribution industry. Gross margin is
calculated by dividing gross profit by net sales.