Basic earnings per share is calculated using the weighted average number of shares of common stock outstanding during the period. Diluted earnings per share is computed in the same manner and also gives effect to all dilutive common stock equivalent shares outstanding during the period. Potential common shares that would have the effect of increasing diluted earnings per share are considered to be anti-dilutive. In accordance with U.S. GAAP, these shares were not included in calculating diluted earnings per share.

For the year ended December 31, 2018, the weighted average number of restricted stock units and stock options excluded from the computation of diluted earnings per share were 52 and 0, respectively. For the year ended December 31, 2017, the weighted average number of restricted stock units and stock options excluded from the computation of diluted earnings per share were 8 and 0, respectively. For the year ended December 31, 2016, the weighted average number of restricted stock units and stock options excluded from the computation of diluted earnings per share were 0 and 39, respectively.

For the years ended December 31, 2017 and 2016, diluted earnings per share-weighted average shares outstanding included the effect resulting from assumed conversion of the Notes and warrants.

	December 31,
	2018		2017		2016
Numerator:
Net income	$	45,096	$	32,909	$	36,952
Denominator:
Basic earnings per share - weighted average shares outstanding		31,671		31,491		31,128
Effect of potential dilutive securities:
Restricted stock units and stock options - dilutive shares		529		670		467
Convertible senior notes - dilutive shares		—		—		103
Warrants - dilutive shares		—		1		92
Diluted earnings per share - weighted average shares outstanding		32,200		32,162		31,790
Earnings per share:
Basic	$	1.42	$	1.05	$	1.19
Diluted	$	1.40	$	1.02	$	1.16