17. Net (loss) income per share attributable to common stockholders

The following table sets forth the computation of basic and diluted net (loss) income per share attributable to common stockholders:

	Years ended December 31,
	2014			2013			2012
	(in thousands)
Numerator:
Net (loss) income attributable to common stockholders, basic and diluted	$	(19,521	)	$	(3,968	)	$	7,295

Denominator:
Weighted average common stock, basic		35,753			35,578			34,774
Effect of dilutive stock options		—			—			2,543

Weighted average common stock, diluted		35,753			35,578			37,317


Net (loss) income per share attributable to common stockholders:
Basic	$	(0.55	)	$	(0.11	)	$	0.21
Diluted	$	(0.55	)	$	(0.11	)	$	0.20

For the years ended December 31, 2014 and 2013, we excluded all stock options and RSUs from the computation of diluted net loss per share due to the net loss for the period. For the year ended December 31, 2012, we excluded approximately 2,518,000 stock options in the computation of diluted net income per share as the inclusion would have been anti-dilutive.