Net Income Per Common Share

6 Months Ended

Jun. 30, 2019

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) and performance stock units (PSUs) as there are no conditions under which those shares will not be issued. Diluted net income per common share is computed by dividing net income by the combination of the weighted average number of common shares outstanding during the period and other potentially dilutive weighted average common shares. Other potentially dilutive weighted average common shares include the dilutive effect of stock options, RSUs, and PSUs for each period using the treasury stock method. Under the treasury stock method, the exercise price of a share and the amount of compensation expense, if any, for future service that has not yet been recognized 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:



	Three Months Ended June 30				Six Months Ended June 30
	2019		2018		2019		2018
	(thousands, except per-share data)
Net income	$	27,718	$	41,825	$	39,107	$	78,875
Weighted average common shares outstanding during the period (for basic calculation)	39,087		38,981		38,986		38,880
Dilutive effect of other potential common shares	112		422		199		504
Weighted average common shares and potential common shares (for diluted calculation)	39,199		39,403		39,185		39,384

Net income per common share - Basic	$	0.71	$	1.07	$	1.00	$	2.03
Net income per common share - Diluted	$	0.71	$	1.06	$	1.00	$	2.00

The computation of the dilutive effect of other potential common shares excludes stock awards representing 0.2 million and no shares of common stock, respectively, in the three months ended June 30, 2019 and 2018, and 0.2 million and 0.1 million of common stock shares, respectively, in the six months ended June 30, 2019 and 2018. Under the treasury stock method, the inclusion of these stock awards would have been antidilutive.