Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share

Schedule of computation of basic and diluted EPS

	Year Ended December 31,
	2011		2010		2009
	(in millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to AGL	$	775.6	$	493.7	$	86.0
Less: Distributed and undistributed income (loss) available to nonvested shareholders		0.5		0.9		0.3
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries	$	775.1	$	492.8	$	85.7
Basic shares		183.4		184.0		126.5
Basic EPS	$	4.23	$	2.68	$	0.68
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries	$	775.1	$	492.8	$	85.7
Plus: Re-allocation of undistributed income (loss) available to nonvested shareholders of AGL and subsidiaries		—		—		—
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries	$	775.1	$	492.8	$	85.7
Basic shares		183.4		184.0		126.5
Effect of dilutive securities:
Options and restricted stock awards		0.9		0.9		0.6
Equity units		1.2		4.0		2.0
Diluted shares		185.5		188.9		129.1
Diluted EPS	$	4.18	$	2.61	$	0.66
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect		7.2		3.0		4.4