Calculation of Earnings per Share

3 Months Ended

Mar. 31, 2012

Earnings Per Share [Abstract]

Calculation of Earnings per Share

Calculation of Earnings per Share

Basic earnings per share is calculated by dividing net income by the weighted-average number of shares outstanding during the period. Diluted earnings per share is calculated by dividing net income attributable to VCA Antech, Inc. by the weighted-average number of common shares outstanding, after giving effect to all dilutive potential common shares outstanding during the period. Basic and diluted earnings per share were calculated as follows (in thousands, except per share amounts):

	Three Months Ended March 31,
	2012		2011
Net income attributable to VCA Antech, Inc	$	35,245	$	28,839
Weighted-average common shares outstanding:
Basic	86,984		86,355
Effect of dilutive potential common shares:
Stock options	560		690
Nonvested shares	511		200
Diluted	88,055		87,245
Basic earnings per share	$	0.41	$	0.33
Diluted earnings per share	$	0.40	$	0.33

For the three months ended March 31, 2012 and 2011, potential common shares of 1,067,063 and 46,270, respectively, were excluded from the computation of diluted earnings per share because their inclusion would have had an antidilutive effect.