Waste Management 2011 Annual Report Download - page 201

WASTE MANAGEMENT, INC.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)
of currently unrecognized compensation expense will be recognized over a weighted average period of 1.8 years
for unvested RSU, PSU and stock option awards issued and outstanding.
Non-Employee Director Plans
Our non-employee directors currently receive annual grants of shares of our common stock, payable in two
equal installments, under the 2009 Plan described above.
17. Earnings Per Share
Basic and diluted earnings per share were computed using the following common share data (shares in millions):
Years Ended December 31,
2011 2010 2009
Number of common shares outstanding at year-end ................... 460.5 475.0 486.1
Effect of using weighted average common shares outstanding ........... 9.2 5.2 5.1
Weighted average basic common shares outstanding .................. 469.7 480.2 491.2
Dilutive effect of equity-based compensation awards and other
contingently issuable shares .................................... 1.7 2.0 2.4
Weighted average diluted common shares outstanding ................. 471.4 482.2 493.6
Potentially issuable shares ....................................... 17.0 12.8 13.2
Number of anti-dilutive potentially issuable shares excluded from diluted
common shares outstanding .................................... 9.8 3.6 0.3
18. Fair Value Measurements
Assets and Liabilities Accounted for at Fair Value
Authoritative guidance associated with fair value measurements provides a framework for measuring fair
value and establishes a fair value hierarchy that prioritizes the inputs used to measure fair value, giving the
highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 inputs)
and the lowest priority to unobservable inputs (Level 3 inputs).
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