Basic net loss per share is calculated by dividing net loss by the weighted-average number of shares outstanding for the period. Diluted net loss per share is calculated by dividing net loss by the weighted-average number of shares of common stock and potential dilutive common stock equivalents outstanding during the period if the effect is dilutive.

The calculation of diluted earnings (loss) per share also requires that, to the extent contingencies are satisfied during the period and the presumed issuance of additional shares as contingent consideration is dilutive to earnings (loss) per share for the period, adjustments to net income or net loss used in the calculation are required to remove the change in fair value of the contingent consideration liability for the period. Likewise, adjustments to the denominator are required to reflect the related dilutive shares. In all periods presented, the Company’s outstanding stock options, RSAs, RSUs (including PSUs), early exercised common stock subject to future vesting, restricted stock accounted for as options, shares subject to the 2018 ESPP and presumed issuance of additional shares as contingent consideration were excluded from the calculation of diluted net loss per share because their effects were antidilutive.

A reconciliation of the numerators and denominators used in computing net loss from continuing operations per share is as follows (in thousands, except per share amounts):

	December 31,
	2021			2020			2019
	(in thousands, except share and per share amounts)
Numerator:
Net loss	$	(60,725	)	$	(93,844	)	$	(82,177	)
Denominator:
Weighted average number of shares outstanding—basic and diluted		55,815,873			50,864,889			43,624,807
Net loss per share—basic and diluted	$	(1.09	)	$	(1.84	)	$	(1.88	)

Since the Company was in a net loss position for all periods presented, basic net loss per common share is the same as diluted net loss per common share as the inclusion of all potential common shares outstanding would have been anti-dilutive.

Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows:

	Year Ended December 31,
	2021		2020		2019
Options to purchase common stock		8,666,955		7,540,472		6,906,898
Early exercised common stock subject to future vesting		33,370		66,741		146,915
RSUs		1,990,937		2,832,077		325,887
PSUs		—		150,000		—
Shares subject to the 2018 ESPP		147,741		111,383		47,597
Total		10,839,003		10,700,673		7,427,297

Up to 55,900 shares may be contingently issued, if certain performance conditions are met under the Company’s in-licensing agreements. See Note 5, “License Revenue, Agreements and Strategic Investment,” to the Company’s financial statements for additional information.