NET INCOME (LOSS) PER COMMON SHARE

Basic net income per common share excludes the dilutive impact of potentially dilutive securities and is computed by dividing net income by the weighted average number of common shares outstanding for the period. Diluted net income per common share includes the effect of potential dilution from the hypothetical exercise of outstanding stock options and vesting of restricted shares and performance shares. A reconciliation of our basic and diluted net income per common share is as follows:



	Three Months Ended September 30,					Nine Months Ended September 30,
(In millions, except per share data)	2018			2017		2018		2017
Net income (loss) to common shareholders	$	(13.1	)	$	54.9	$	131.7	$	98.2
Basic weighted average shares outstanding	238.7			240.7		239.9		240.5
Diluted weighted average shares outstanding	238.7			245.8		244.2		246.2
Net income (loss) per common share:
Basic net income (loss) per share	$	(0.05	)	$	0.23	$	0.55	$	0.41
Diluted net income (loss) per share	$	(0.05	)	$	0.22	$	0.54	$	0.40

The number of anti-dilutive shares that have been excluded in the computation of diluted net income (loss) per share for the three and nine months ended September 30, 2018 were 8.8 million and 2.6 million, respectively. The number of anti-dilutive shares that have been excluded in the computation of diluted net income (loss) per share for the three and nine months ended September 30, 2017 were 1.9 million and 1.8 million, respectively.