Net Loss Per Share

Basic loss per common share is determined by dividing loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted loss per share is computed by dividing the loss attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period. The treasury stock method is used to determine the dilutive effect of the Company's stock option grants. 5,315,477 stock options (common stock equivalents) were excluded from the calculation of diluted loss per share for the three months ended March 31, 2018 because their inclusion would have been anti-dilutive. 4,743,518 stock options were excluded from the calculation of diluted loss per share for the three months ended March 31, 2017 because their inclusion would have been anti-dilutive.

Basic and diluted loss per common share is computed as follows (in thousands except share and per share data):



	Three Months Ended March 31,
	2018			2017
Numerator:
Net loss used for calculation of basic and diluted EPS	$	(49,536	)	$	(37,655	)

Denominator:
Weighted average shares outstanding, basic	36,936,560			34,958,228
Effect of dilutive securities:
Stock options and restricted stock units	—			—
Weighted average shares outstanding, diluted	36,936,560			34,958,228

Net loss per share, basic and diluted	$	(1.34	)	$	(1.08	)