8. Loss Per Share

Basic net loss per common share is computed by dividing the net loss available to common stockholders by the weighted average number of common shares outstanding during the period. Diluted net loss per common share is computed by dividing the net loss available to common stockholders by the weighted average number of common shares and other potential common shares then outstanding. Potential common shares consist of common shares issuable upon the assumed exercise of in-the-money stock options and warrants and potential common shares related to the conversion of the preferred stock. The computation of diluted net loss per share does not assume the issuance of common shares that have an anti-dilutive effect on net loss per share.


	Year Ended December 31,
	(in thousands, except share and per share amounts)
	2016			2015
Net loss	$	(21,436	)	$	(20,027	)
Preferred stock dividends		(741	)		(868	)
Preferred stock accretion		(173	)		(229	)

Net loss applicable to common stockholders	$	(22,350	)	$	(21,124	)

Basic and diluted net loss per share	$	(0.76	)	$	(0.88	)
Shares used in computing basic and diluted net loss per share		29,216			24,120

Dilutive shares which could exist pursuant to the exercise of outstanding stock instruments and which were not included in the calculation because their affect would have been anti-dilutive are as follows:


	Year Ended December 31,
	2016 (Shares)		2015 (Shares)
Warrants to purchase shares of common stock		13,488,296		8,908,586
Options to purchase shares of common stock		4,656,888		3,342,325
Shares of common stock issuable upon conversion preferred stock		4,312,282		2,522,936

		22,457,466		14,807,681