5.	Net income (loss) per common share:

Basic net income (loss) per common share is computed by dividing the net income (loss) by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per common share is computed by adjusting the numerator and denominator of the basic net income (loss) per share calculation for the potential impact of dilutive securities.

For the year ended December 31, 2017, 2,172,034 stock options and warrants were excluded from the calculation of diluted net income per common share as their inclusion would be anti-dilutive. For the years ended December 31, 2016 and December 31, 2015, all stock options were anti-dilutive and were excluded from the diluted weighted average common shares outstanding for those periods.

The following is a reconciliation of the numerators and denominators of basic and diluted net loss per common share:

	Year Ended December 31,
	2017			2016			2015
Numerator:
Net loss used to compute net loss per common share:
Basic	$	(30,704	)	$	(22,997	)	$	(15,752	)
Adjustment for change in fair value of liability classified stock options		(187	)		—			—
Diluted	$	(30,891	)	$	(22,997	)	$	(15,752	)
Denominator:
Weighted average number of common shares:
Basic		17,985,061			15,493,474			14,281,837
Adjustment for dilutive effect of stock options		16,698			—			—
Diluted		18,001,759			15,493,474			14,281,837
Net loss per common share - basic	$	(1.71	)	$	(1.48	)	$	(1.10	)
Net loss per common share - diluted	$	(1.72	)	$	(1.48	)	$	(1.10	)