Net Income (Loss) Per Share

Basic earnings (loss) per share is computed by dividing net income by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income by the weighted-average number of common shares outstanding during the period plus dilutive securities. Dilutive securities include outstanding common stock options and unvested restricted stock units, less the number of shares that could have been purchased with the proceeds from the exercise of the options, using the treasury stock method. Options that are anti-dilutive, where their exercise price exceeds the average market price of the common stock are not included in the treasury stock method calculation. There were 18 and 48 anti-dilutive securities for the three months ended September 30, 2018 and 2017, respectively. There were 3,694 and 590 anti-dilutive securities for the nine months ended September 30, 2018 and 2017, respectively.

The following table presents the calculation of net earnings per common share (“EPS”) — basic and diluted (in thousands, except per share data):



	Three months ended September 30,				Nine months ended September 30,
	2018		2017		2018		2017
Net income	$	219	$	136	$	36,148	$	18,939
Weighted-average number of common shares outstanding (for basic calculation)	20,474		19,984		20,362		19,433
Dilutive securities	1,159		1,122		1,226		1,170
Weighted-average common and common equivalent shares outstanding (for diluted calculation)	21,633		21,106		21,588		20,603
EPS — basic	$	0.01	$	0.01	$	1.78	$	0.97
EPS — diluted	$	0.01	$	0.01	$	1.67	$	0.92