NET INCOME (LOSS) PER SHARE

12 Months Ended

Dec. 31, 2019

Basic net income (loss) per share is computed by dividing the net income (loss) by the weighted-average number of shares of common stock outstanding during the period. Diluted net income (loss) per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding adjusted for the dilutive effect of all potential shares of common stock. In the years when the Company reported a net loss, diluted loss per share is the same as basic loss per share because the effects of potentially dilutive items were anti-dilutive.

The following table presents the calculation of basic and diluted net income (loss) per share (in thousands, except per share data):


	Year Ended December 31,
	2019		2018		2017
Net income (loss)	$	375,446	$	(38,453)	$	(62,813)
Basic shares:
Weighted-average common shares outstanding	425,728		406,313		380,921
Weighted-average unvested shares	(729)		(582)		(1,577)
Weighted-average shares used to compute basic net income (loss) per share	424,999		405,731		379,344
Diluted shares:
Stock options and restricted stock units	30,602		—		—
Convertible senior notes	—		—		—
Common stock warrants	10,432		—		—
Employee stock purchase plan	43		—		—
Weighted-average shares used to compute diluted net income (loss) per share	$	466,076	$	405,731	$	379,344

Net income (loss) per share:
Basic	$	0.88	$	(0.09)	$	(0.17)
Diluted	$	0.81	$	(0.09)	$	(0.17)

The following potential common shares were excluded from the calculation of diluted net income (loss) per share because their effect would have been anti-dilutive for the periods presented (in thousands):


	Year Ended December 31,
	2019	2018	2017
Stock options and restricted stock units	13,867	60,589	68,588
Common stock warrants	19,820	25,798	19,173


Convertible senior notes	20,305	23,820	—
Unvested shares	728	582	1,300
Employee stock purchase plan	165	140	157
Total anti-dilutive securities	54,885	110,929	89,218