Net Income (Loss) Per Common Share

Basic and diluted net income (loss) per common share is determined by dividing net income (loss) by the weighted average common shares outstanding during the period. For the periods when there is a net loss, stock options and RSUs have been excluded from the calculation of diluted net loss per common share because their effect would be anti-dilutive. Therefore, the weighted average common shares used to calculate both basic and diluted net loss per common share would be the same. The following table sets forth the computation of basic and diluted net income (loss) per common share for the periods indicated:



	Years ended December 31,
	2018		2017		2016
Basic and diluted net income (loss) per common share calculation:
Net income (loss)	$	63,087	$	114,205	$	(193,420	)
Weighted average common shares outstanding - basic	37,061		35,919		35,486
Plus: net effect of dilutive stock options and unvested restricted stock units	27		88		—
Weighted average common shares outstanding - dilutive	37,088		36,007		35,486
Net income (loss) per common share - basic	$	1.70	$	3.18	$	(5.45	)
Net income (loss) per common share - diluted	$	1.70	$	3.17	$	(5.45	)

The following potentially dilutive securities have been excluded from the computations of diluted weighted average common shares outstanding for the periods presented, as they would be anti-dilutive:



	Years ended December 31,
	2018	2017	2016
Stock options outstanding	5,873	5,179	3,359
Restricted stock units	601	182	721
Total	6,474	5,361	4,080