Net Income (Loss) per Share Attributable to Common Stock:

Net income (loss) per share attributable to common stock is computed by dividing the net income (loss) attributable to common stock by the weighted-average number of common shares outstanding. The Company has outstanding stock options and redeemable convertible preferred stock, which are included in the calculation of diluted net income (loss) attributable to common stock per share whenever doing so would be dilutive.

The Company calculates basic and diluted net income (loss) per share attributable to common stock in conformity with the two-class method required for companies with participating securities. The Company considers all series of redeemable convertible preferred stock to be participating securities. Under the two-class method, net loss attributable to common stock is not allocated to the redeemable convertible preferred stock as the holders of redeemable convertible preferred stock do not have a contractual obligation to share in losses. Upon the conversion of the redeemable convertible preferred stock to common stock on the date of the IPO, or August 2nd, 2017, the Company only had one class of participating security, common stock.

Diluted net income (loss) per share attributable to common stock is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period. For purposes of this calculation, redeemable convertible preferred stock and options to purchase common stock are considered anti-dilutive securities for all periods presented. Basic and diluted net income (loss) per share attributable to common stock was the same for each period presented.

The following table sets forth the calculation of basic and diluted net income (loss) per share attributable to common stock during the periods presented:



	Year End December 31,
	2015			2016			2017

Numerator:
Net income (loss)	$	(30,236	)	$	(22,526	)	$	(15,002	)
Accretion of preferred stock	(102,224		)	(55,502		)	(175,915		)
Net income (loss) attributable to common stock—basic and diluted	$	(132,460	)	$	(78,028	)	$	(190,917	)

Denominator:
Weighted average shares used to compute net income (loss) per share attributable to common stock—basic and diluted	13,416,411			14,395,067			42,722,114
Net income (loss) per share attributable to common stock—basic and diluted	$	(9.87	)	$	(5.42	)	$	(4.47	)

The following outstanding shares of common stock equivalents were excluded from the computation of the diluted net income (loss) per share attributable to common stock for the periods presented because their effect would have been anti-dilutive. For the year ended December 31, 2017 shares of the redeemable convertible preferred stock were anti-dilutive, but converted to common stock on a one-for-one basis on August 2, 2017 upon the successful completion of the IPO, and as such were included in the weighted average shares outstanding for the period they were outstanding as shares of common stock.



	Year End December 31,
	2015	2016	2017

Redeemable convertible preferred stock	55,422,002	55,422,002	—
Options outstanding	10,406,277	13,291,684	13,180,950
Restricted stock units	—	—	981,276
Total	65,828,279	68,713,686	14,162,226