Net Income Per Share

12 Months Ended

Dec. 31, 2015

The calculation of net income per share for the three years ended December 31, 2015 is reflected in the following table (in thousands, except per share amounts):



	Years Ended December 31,
	2015		2014		2013
Basic net income per share:
Net income	$	357,796	$	305,928	$	252,195
Income allocated to participating securities	—		—		3
Net income available to common stockholders	$	357,796	$	305,928	$	252,192
Basic weighted average shares	131,749		134,358		136,153
Basic net income per share	$	2.72	$	2.28	$	1.85
Diluted net income per share:
Net income	$	357,796	$	305,928	$	252,195
Income allocated to participating securities	—		—		3
Net income available to common stockholders	$	357,796	$	305,928	$	252,192
Basic weighted average shares	131,749		134,358		136,153
Dilutive effect of potential common shares	1,181		1,183		1,436
Diluted weighted average shares	132,930		135,541		137,589
Diluted net income per share	$	2.69	$	2.26	$	1.83

Potential common shares include the dilutive effect of stock options, unvested performance-based restricted stock, restricted stock which contains forfeitable rights to dividends, and stock units.

Employee stock options will have a dilutive effect under the treasury method only when the respective period’s average market value of the Company’s common stock exceeds the exercise proceeds. Under the treasury method, exercise proceeds include the amount the employee must pay for exercising stock options, the amount of compensation cost for future service that the Company has not yet recognized, and the amount of tax benefits that would be recorded in capital surplus, if the options were exercised and the stock units and performance-based restricted stock had vested.