Net Income Per Common Share

12 Months Ended

Dec. 31, 2015

Basic net income per common share is computed by dividing net income by the weighted average number of common shares outstanding during the period. Weighted average common shares outstanding for the basic net income per common share calculation includes certain vested restricted stock units (RSUs) as there are no conditions under which those shares will not be issued. For more information about common share activity during the period, see Note 9, Stockholders' Equity. Diluted net income per common share is computed by dividing net income by the combination of other potentially dilutive weighted average common shares and the weighted average number of common shares outstanding during the period. Other potentially dilutive weighted average common shares include the dilutive effect of stock options, RSUs, and performance stock units (PSUs) for each period using the treasury stock method. Under the treasury stock method, the exercise price of a share, the amount of compensation expense, if any, for future service that has not yet been recognized, and the amount of tax benefits that would be recorded in additional paid-in-capital, if any, when the share is exercised are assumed to be used to repurchase shares in the current period.

The following table sets forth the computation of basic and diluted net income per common share:



	Year Ended December 31
	2015		2014		2013
	(thousands, except per-share data)
Net income	$	52,182	$	80,009	$	116,936
Weighted average common shares outstanding during the period (for basic calculation)	39,239		39,412		40,203
Dilutive effect of other potential common shares	116		80		23
Weighted average common shares and potential common shares (for diluted calculation)	39,355		39,492		40,226

Net income per common share - Basic	$	1.33	$	2.03	$	2.91
Net income per common share - Diluted	$	1.33	$	2.03	$	2.91

The computation of the dilutive effect of other potential common shares excludes stock awards representing 0.1 million, 0.2 million, and 0.1 million shares of common stock in the years ended December 31, 2015, 2014, and 2013, respectively. Under the treasury stock method, the inclusion of these stock awards would have been antidilutive.