Earnings Per Share

6 Months Ended

Jun. 30, 2011

2. Earnings Per Share

The following table sets forth the computation of basic and diluted earnings per share on net income (in thousands, except per share information):

				Three months ended				Six months ended
			June 30,				June 30,
				2011		2010		2011		2010
Earnings:
	Net income (numerator for basic and diluted calculations)		$	132,888	$	127,019	$	293,704	$	249,458
Shares:
	Weighted average outstanding shares (denominator for
		basic calculation)		73,971		73,141		73,593		73,094
	Equivalent shares from outstanding stock options⁽¹⁾			559		1,580		591		1,556
	Denominator for diluted calculation			74,530		74,721		74,184		74,650
Earnings per share:
	Basic		$	1.80	$	1.74	$	3.99	$	3.41
	Diluted		$	1.78	$	1.70	$	3.96	$	3.34
	(1) Year-to-date amounts are weighted average of the individual quarterly amounts.

The calculation of common equivalent shares does not include the impact of options having a strike or conversion price that exceeds the average stock price for the earnings period, as the result would be antidilutive. The calculation of common equivalent shares also excludes the impact of outstanding performance contingent shares, as the conditions necessary for their issuance have not been satisfied as of the end of the reporting period. For the three months ended June 30, 2011, no stock options and approximately 0.8 million performance contingent shares were excluded from the calculation. For the three months ended June 30, 2010, approximately 0.7 million stock options and approximately 0.7 million performance contingent shares were excluded from the calculation.