Weighted Average Shares

12 Months Ended

Dec. 31, 2016

Weighted-average shares were calculated as follows (in thousands):



	Year Ended December 31,
	2016	2015	2014
Basic weighted-average common shares outstanding	85,338	86,296	86,858
Effect of dilutive stock options	1,734	1,695	2,213
Diluted weighted-average common and common-equivalent shares outstanding	87,072	87,991	89,071

Stock options to purchase 2,195,799, 3,035,078, and 1,286,403 shares of common stock, on a weighted-average basis, were outstanding in 2016, 2015, and 2014, respectively, but were not included in the calculation of dilutive net income per share because they were anti-dilutive.