Net Loss Per Share

Basic net loss per share is calculated by dividing net loss by the weighted average number of shares of common stock outstanding during the period, and excludes any dilutive effects of employee stock-based awards and warrants. Diluted net income per share is computed giving effect to all potentially dilutive common shares, including common stock issuable upon exercise of stock options and warrants and vesting of restricted stock. As the Company had net losses for the years ended December 31, 2017, 2016 and 2015, all potentially issuable common shares were determined to be anti-dilutive.

The following table presents the calculation of basic and diluted net loss per share (in thousands, except per share data).



	Year Ended December 31,
	2017			2016			2015
Net loss	$	(8,969	)	$	(11,860	)	$	(25,838	)
Weighted-average shares used in computing basic and diluted net loss per share	54,946			52,342			50,141
Basic and diluted net loss per share	$	(0.16	)	$	(0.23	)	$	(0.52	)

The following securities were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive (in thousands).



	December 31,
	2017	2016	2015
Stock options	4,047	5,556	6,092
Restricted stock units	2,033	2,019	1,818
ESPP	—	—	156
Common stock warrants	13	132	191
Total	6,093	7,707	8,257