Redeemable Convertible Preferred Stock and Stockholders’ Equity

Redeemable Convertible Preferred Stock—The Company's redeemable convertible preferred stock automatically converted into common stock at a rate of one-for-one on the closing of the Company's IPO on August 2, 2017. As such, no shares of redeemable convertible preferred stock were authorized, issued and outstanding as of March 31, 2018.

Please see Note 6 to the Company's consolidated financial statements in its Annual Report on Form 10-K for the fiscal year ended December 31, 2017 for a description of the terms of the redeemable convertible preferred stock.

Accretion Expense—Accretion represents the increase in the redemption value of the Company’s redeemable convertible preferred stock. The recognized accretion expense related to the increase in the redemption value of the redeemable convertible preferred stock was reclassed upon the successful completion of the IPO, which occurred during 2017.

Significant unobservable inputs used in the determination of fair value of the Company’s redeemable convertible preferred stock for the three months ended March 31, 2017, when outstanding, included the following:



	Three Months Ended March 31, 2017

Valuation methodology:
Income approach (private company)	12.5%
Market approach (private company)	12.5%
PWERM (IPO)	60.0%
PWERM (M&A)	15.0%
IPO revenue multiple	2.8x-3.0x
Forecasted revenue growth rate	31.1%-40.0%
Discount rate	20.0%

The following table presents the accretion expense of the redeemable convertible preferred stock to its redemption value recorded within the consolidated statements of changes in redeemable convertible preferred stock and stockholders’ equity during the three months ended March 31, 2017:



	Three Months Ended March 31, 2017

Series A-1	$	(701	)
Series A-2	(18		)
Series A-3	(1,365		)
Series B	(5,451		)
Series C	(5,008		)
Series D	(4,286		)
Series E	(1,806		)
Series F	(3,121		)
Series G	(3,014		)
Total	$	(24,770	)

Common Stock—At March 31, 2018 and December 31, 2017, the Company was authorized to issue 500,000,000 shares of common stock with a par value of $0.001 per share.

The Company has reserved shares of common stock, on an as-converted basis, for future issuance as follows:



	March 31, 2018	December 31, 2017

2017 Equity Incentive Plan:
Stock options issued and outstanding	11,821,024	13,180,950
Restricted stock units outstanding	1,152,718	981,276
Shares available for future equity grants	7,011,507	7,026,071
Total	19,985,249	21,188,297

2017 Employee Stock Purchase Plan:
Shares reserved under employee stock purchase plan	2,414,688	1,600,000
Total	2,414,688	1,600,000

Preferred Stock—As of March 31, 2018 and December 31, 2017, the Company had authorized 10,000,000 shares of preferred stock, par value $0.001, of which no shares were outstanding.