Earnings Per Share

The following table sets forth the computation of basic and diluted earnings per share (EPS):



	Year Ended December 31,
	2017		2016		2015
	(in thousands, except per share data)
Net income available to common shareholders	$	57,298	$	31,770	$	12,678

Weighted average common shares outstanding - Basic	38,655		38,207		38,224
Dilutive effect of stock-based awards	732		436		282
Weighted average common shares outstanding - Diluted	39,387		38,643		38,506
Earnings per common share - Basic	$	1.48	$	0.83	$	0.33
Earnings per common share - Diluted	$	1.45	$	0.82	$	0.33

Stock-based Awards

For stock-based awards, the dilutive effect is calculated using the treasury stock method. Under this method, the dilutive effect is computed as if the awards were exercised at the beginning of the period (or at time of issuance, if later) and assumes the related proceeds were used to repurchase common stock at the average market price during the period. Related proceeds include the amount the employee must pay upon exercise and future compensation cost associated with the stock award. Approximately 0.2 million, 0.7 million, and 1.2 million stock-based awards were excluded from the calculation of diluted EPS for the years ended December 31, 2017, 2016, and 2015, respectively, because they were anti-dilutive. These stock-based awards could be dilutive in future periods.