Earnings Per Share

Basic earnings per share is computed by dividing net income by the weighted average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income by the weighted average number of common shares outstanding plus the effect of dilutive potential common shares outstanding during the period using the treasury stock method. Dilutive potential common shares include outstanding stock options and restricted stock awards. There are no differences in the numerators of our computations of basic and diluted earnings per share for any periods presented.

The computation of basic and diluted earnings per share is shown below (in thousands, except per share amounts).



	Three Months Ended March 31,
	2019		2018
Net income	$	36,086	$	27,807
Weighted average common shares outstanding	70,274		72,435
Dilutive effect of stock-based awards	298		236
Shares used in computing diluted earnings per share	70,572		72,671
Basic earnings per share	$	0.51	$	0.38
Diluted earnings per share	$	0.51	$	0.38

There were no options to purchase shares of common stock that were outstanding during the periods indicated above that were excluded from the computation of diluted earnings per share because the option purchase price was greater than the average market price of the common shares during the period. Performance awards are excluded from the calculation of dilutive potential common shares until the threshold performance conditions have been satisfied.