Net Loss per Share

12 Months Ended

Dec. 31, 2015

9. Net Loss per Share

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


	Year Ended
	December 31,
	2015		2014		2013
Numerator:
Net loss	$	(20,563)	$	(8,517)	$	(5,236)
Accretion of redeemable convertible preferred stock to redemption value		(2,566)		(2,054)		(1,740)
Net loss attributable to common stockholders	$	(23,129)	$	(10,571)	$	(6,976)
Denominator:
Weighted average shares of common stock outstanding		6,637,678		2,730,427		2,730,427
Less: Weighted average shares of unvested restricted common stock outstanding		(530,636)		(1,010,345)		(1,649,080)
Weighted average common shares outstanding used in calculating net loss per share attributable to common stockholders, basic and diluted		6,107,042		1,720,082		1,081,347
Net loss per share attributable to common stockholders, basic and diluted	$	(3.79)	$	(6.15)	$	(6.45)

To calculate net loss attributable to common stockholders for the period, 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 include stock options, RSUs, unvested restricted common stock and convertible preferred stock, have been excluded from the computation of diluted net loss per share as 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 potential common shares, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share attributable to common stockholders for the periods indicated:


	Year Ended December 31,
	2015	2014	2013

Stock options to purchase common stock	1,738,524	500,262	—
Restricted stock unit awards	53,800	—	—
Unvested restricted common stock	—	759,538	1,239,247
Convertible preferred stock (as converted to common stock)	—	7,924,919	6,055,060
	1,792,324	9,184,719	7,294,307