EARNINGS PER SHARE

12 Months Ended

Dec. 31, 2019

EARNINGS PER SHAREUnvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are participating securities and are included in the computation of earnings per share pursuant to the two-class method for all periods presented. The Company’s service-based restricted stock awards contain non-forfeitable rights to dividends and are participating securities. The two-class method is an earnings allocation formula that treats a participating security as having rights to undistributed earnings that would otherwise have been available to common stockholders. Accordingly, service-based restricted stock awards were included in the calculation of earnings per share using the two-class method for all periods presented. Unvested service-based restricted shares totaled approximately 0.7

million at December 31, 2019 and 2018, and 0.6 million at December 31, 2017. Basic earnings per share is calculated by first allocating earnings between common stockholders and participating securities. Earnings attributable to common stockholders are divided by the weighted average number of common shares outstanding during the period. Diluted earnings per share is calculated by giving effect to dilutive potential common shares outstanding during the period. The dilutive effect of shares related to the Company’s employee stock purchase plan is determined based on the treasury stock method. The dilutive effect of service-based restricted stock awards is based on the more dilutive of the treasury stock method or the two-class method assuming a reallocation of undistributed earnings to common stockholders after considering the dilutive effect of potential common shares other than the participating unvested restricted stock awards. The dilutive effect of performance-based restricted stock awards is based on the treasury stock method.

The following table sets forth the computation of basic and diluted earnings per share (in thousands, except per share amounts):


	December 31,
	2019		2018		2017
Numerator:
Net income	$	50,430	$	58,269	$	51,614
Less: Income allocated to participating securities	(546)		(629)		(479)
Net income available to common stockholders	$	49,884	$	57,640	$	51,135
Denominator:
Weighted average shares - basic	66,884		66,499		66,209
Performance-based restricted stock awards	—		61		57
Weighted average shares - diluted	66,884		66,560		66,266

Basic net income per share:	$	0.75	$	0.87	$	0.77

Diluted net income per share:	$	0.75	$	0.87	$	0.77