Net loss per common stock

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Net loss per common stock

9. Net loss per common stock

Basic and diluted net loss per common stock is computed by dividing net loss by the weighted average number of common stock outstanding. The Company excluded outstanding stock options and common stock warrants from the calculation of basic and diluted net loss per common stock as the effect would have been antidilutive for all periods presented.

The following have been excluded from the computation of basic and diluted net loss per common stock as their effect would have been antidilutive:

	DECEMBER 31, 2017		DECEMBER 31, 2016		DECEMBER 31, 2015
Outstanding stock options		2,069,167		1,378,352		865,457
Common stock warrants		—		—		11,363
Total		2,069,167		1,378,352		876,820