Net Loss per Share

12 Months Ended

Dec. 31, 2016

8. Net Loss per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Year Ended
	December 31,
	2016		2015		2014
Numerator:
Net loss	$	(48,079)	$	(20,563)	$	(8,517)
Accretion of redeemable convertible preferred stock		—		(2,566)		(2,054)
Net loss attributable to common stockholders	$	(48,079)	$	(23,129)	$	(10,571)
Denominator:
Weighted average shares of common stock outstanding		21,415,733		6,637,678		2,730,427
Less: Weighted average shares of unvested restricted common stock outstanding		—		(530,636)		(1,010,345)
Weighted average common shares outstanding used in calculating net loss per share attributable to common stockholders, basic and diluted		21,415,733		6,107,042		1,720,082
Net loss per share attributable to common stockholders, basic and diluted	$	(2.25)	$	(3.79)	$	(6.15)

To calculate net loss attributable to common stockholders the Company reduced the net loss for the accretion of issuance costs and cumulative dividends accrued but not paid through August 28, 2015, and the remaining cumulative dividends accrued but not paid through October 13, 2015, the date on which all convertible preferred stock converted to common stock.

The Company’s potential dilutive securities, which included stock options, RSUs, preferred stock, and shares of restricted common stock that were issued but not yet vested, have been excluded from the computation of diluted net loss per share since the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The following table presents potential common shares excluded from the calculation of diluted net loss per share attributable to common stockholders for the years ended December 31, 2016, 2015 and 2014. All share amounts presented in the table below represent the total number outstanding as of December 31.


	2016	2015	2014

Stock options to purchase common stock	2,702,350	1,738,524	500,262
Restricted stock unit awards	219,614	53,800	—
Unvested restricted common stock	—	—	759,538
Convertible preferred stock (as converted to common stock)	—	—	7,924,919
	2,921,964	1,792,324	9,184,719