(13)NET INCOME PER SHARE

The following table sets forth the computation of basic and diluted shares for the periods indicated (in thousands):


	Three Months Ended September 30,		Nine Months Ended September 30,
	2018	2017	2018	2017

Shares used in basic earnings per share calculation	46,172	45,838	46,021	45,816
Effect of dilutive securities:
Stock options	6	10	8	9
Restricted stock units	138	517	360	513
Performance-based restricted stock units	—	2	1	10
Total effects of dilutive securities	144	529	369	532
Shares used in dilutive earnings per share calculation	46,316	46,367	46,390	46,348

For the three months ended September 30, 2018 and 2017, no options to purchase shares of common stock were outstanding but not included in the computation of diluted net income per share because the exercise price exceeded the value of the shares and the effect would have been anti-dilutive. For the nine months ended September 30, 2018 and 2017, no options and 30 thousand options to purchase shares of common stock, respectively, were outstanding, but not included in the computation of diluted net income per share because the exercise price exceeded the value of the shares and the effect would have been anti-dilutive. For the three months ended September 30, 2018 and 2017, restricted stock units (“RSUs”) of 475 thousand and two thousand, respectively, were outstanding, but not included in the computation of diluted net income per share because the effect would have been anti-dilutive. For the nine months ended September 30, 2018 and 2017, RSUs of 168 thousand and 16 thousand, respectively, were outstanding, but not included in the computation of diluted net income per share because the effect would have been anti-dilutive.