Note 5. Computation of Net Earnings per Share

Basic earnings per share is computed by dividing income available to common stockholders (the numerator) by the weighted‑average number of common shares outstanding (the denominator) for the period. The computation of diluted earnings per share is similar to basic earnings per share, except that the denominator is increased by the number of additional common shares that would have been outstanding if the potentially dilutive common shares issuable for stock options and RSUs had been issued, calculated using the treasury stock method.

The components of net earnings per share are as follows:


	Three months ended				Nine months ended
	September 30,				September 30,
	2019		2018		2019		2018
	(in thousands, except per share amounts)
Net income available to common stockholders	$	704	$	8,838	$	7,322	$	37,422
Weighted average common shares outstanding used in computing basic income per share		32,344		32,365		32,584		32,225
Incremental options and RSUs		979		1,608		1,237		1,807
Weighted average common shares used in computing diluted net income per share		33,323		33,973		33,821		34,032
Net income per share
Basic	$	0.02	$	0.27	$	0.22	$	1.16
Diluted	$	0.02	$	0.26	$	0.22	$	1.10

Diluted weighted average common shares outstanding does not include options and RSUs outstanding to purchase 0.8 million and 0.3 million common equivalent shares for the three month periods ended September 30, 2019 and 2018, respectively, nor options and RSUs outstanding to purchase 0.2 million and eleven thousand common equivalent shares for the nine month periods ended September 30, 2019 and 2018, respectively, as their effect would have been anti-dilutive.