Net Earnings Per Share

3 Months Ended

Mar. 31, 2012

Net Earnings Per Share

Net Earnings Per Share

6.     Net Earnings Per Share

        Net earnings per share were computed as follows:

	Three months ended March 31,
	2012		2011
	(in millions, except per share amounts)
Net earnings attributable to common stockholders	$	368.4	$	282.0
Basic earnings per common share:
Weighted average common shares outstanding		65.5		71.3
Net earnings attributable to common stockholders	$	5.62	$	3.95
Diluted earnings per common share:
Weighted average common shares outstanding		65.5		71.3
Dilutive common shares—stock options		1.0		0.8
Diluted weighted average shares outstanding		66.5		72.1
Net earnings attributable to common stockholders	$	5.54	$	3.91

        In the computation of diluted net earnings per common share, potentially dilutive stock options are excluded if the effect of their inclusion is anti-dilutive. For the three months ended March 31, 2012 and 2011, anti-dilutive stock options were insignificant.