Earnings Per Share

9 Months Ended

Sep. 30, 2011

4.	Earnings Per Share

The Company's basic earnings per share calculations are based on the weighted average number of common shares outstanding during the year. Shares of restricted stock are included in the computation of both basic and diluted earnings per share. Potentially dilutive securities include outstanding stock options, restricted share units and deferred stock units. The dilutive effect of potentially dilutive securities is reflected in diluted earnings per common share by application of the treasury method. Diluted earnings per share gives effect to all potentially dilutive common shares outstanding during the year.


	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands, except per share data)	2011		2010		2011		2010

Net income attributable to common shareholders	$	52,540	$	41,507	$	151,444	$	114,782


Average basic shares outstanding		58,048		58,608		58,202		58,710
Effect of dilutive stock options		1,010		917		1,128		935

Average diluted shares outstanding		59,058		59,525		59,330		59,645


Earnings per basic share	$	0.91	$	0.71	$	2.60	$	1.96
Earnings per diluted share	$	0.89	$	0.70	$	2.55	$	1.92

The computation of diluted earnings per share excludes the effect of the potential exercise of stock options when the average market price of the common stock is lower than the exercise price of the related stock options during the period (1.0 million and 2.0 million average options for the third quarter of 2011 and 2010, respectively, and 0.8 million and 2.6 million average options for the first nine months of 2011 and 2010, respectively).