Net Income Per Share

9 Months Ended

Sep. 30, 2011

Note 8: Net Income Per Share

The following table reconciles net income and shares used in the calculation of basic net income per share to those used for diluted net income per share:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
($ in millions)	2011		2010		2011		2010
Net income, as reported, for basic net income per share	$	16.9	$	17.8	$	56.7	$	59.3
Plus: interest expense on convertible debt, net of tax		1.1		1.1		3.2		3.2
Net income for diluted net income per share	$	18.0	$	18.9	$	59.9	$	62.5

Weighted average common shares outstanding	33.8	33.4	33.6	33.3
Assumed stock options exercised and awards vested, based on the treasury stock method	0.3	0.4	0.5	0.5
Assumed conversion of convertible debt, based on the if-converted method	2.9	2.9	2.9	2.9
Weighted average shares assuming dilution	37.0	36.7	37.0	36.7

Options to purchase 1.7 million shares of our common stock for both of the three month periods ended September 30, 2011 and 2010 were not included in the computation of diluted net income per share because their impact would be antidilutive. There were 1.3 million and 1.1 million antidilutive options outstanding during the nine month periods ended September 30, 2011 and 2010, respectively.