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.

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 ended June 30, 2017. For the periods ended June 30, 2016 the inclusion of the Company's redeemable convertible preferred stock was dilutive. For the periods ended June 30, 2016 the fair value of the redeemable convertible preferred stock declined, resulting in accretion income. The if-converted method of calculating earnings per share resulted in undistributed earnings attributable to participating securities, and conversion of redeemable convertible preferred stock occurring at the beginning of the period. The undistributed earnings attributable to participating securities do not represent a distribution to existing stockholders' paid out of offering proceeds. Options were excluded in the calculation of weighted average shares used to compute diluted income (loss) for all periods presented except the three months ended June 30, 2016.

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



	Three Months Ended June 30,						Six Months Ended June 30,
	2016			2017			2016			2017

Numerator:
Net income (loss)	$	1,388		$	4,304		$	(22,893	)	$	(23,762	)
Accretion of redeemable convertible preferred stock	65,082			(110,921		)	59,869			(135,690		)
Undistributed earnings attributable to participating securities	(52,805		)	—			(29,397		)	—
Net income (loss) attributable to common stock—basic	13,665			(106,617		)	7,579			(159,452		)
Net income (loss) attributable to common stock—diluted	1,388			(106,617		)	(22,893		)	(159,452		)

Denominator:
Weighted average shares used to compute net income (loss) per share attributable to common stock—basic	14,340,333			14,913,234			14,288,550			14,840,759
Weighted average shares used to compute net income (loss) per share attributable to common stock—diluted	74,080,026			14,913,234			69,710,552			14,840,759
Net income (loss) per share attributable to common stock—basic	$	0.95		$	(7.15	)	$	0.53		$	(10.74	)
Net income (loss) per share attributable to common stock—diluted	$	0.02		$	(7.15	)	$	(0.33	)	$	(10.74	)

(1) A reconciliation of net income (loss) attributable to common stock—basic to net income (loss) attributable to common stock—diluted is as follows:
Net income (loss) attributable to common stock—basic	$	13,665					$	7,579
Add-back: Accretion due to application of if-converted	(65,082		)				(59,869		)
Add-back: Undistributed earnings attributable to participating securities due to application of if-converted	52,805						29,397
Net income (loss) attributable to common stock—diluted	$	1,388					$	(22,893	)

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:



	Three Months Ended June 30,		Six Months Ended June 30,
	2016	2017	2016	2017

Redeemable convertible preferred stock	—	55,422,002	—	55,422,002
Options outstanding	4,205,443	13,782,401	11,614,015	13,782,401
Total	4,205,443	69,204,403	11,614,015	69,204,403