15.

Earnings per common share:

The following is a reconciliation of the numerators and denominators of the basic and diluted earnings per common share computations for the years ended December 31, 2017, 2016 and 2015.


	December 31,
	2017		2016			2015
Basic:
Net income (loss) attributable to common stockholders	$	5,285	$	(67,138	)	$	(37,672	)
Weighted average common shares outstanding		55,355,802		53,679,134			52,384,876

Basic earnings (loss) per common share	$	0.10	$	(1.25	)	$	(0.72	)


Diluted:
Effect of dilutive securities:
Net income (loss) attributable to common stockholders		5,285		(67,138	)		(37,672	)
Adjustment to income for dilutive options and warrants		—		—			—

		5,285		(67,138	)		(37,672	)
Weighted average common shares outstanding		55,355,802		53,679,134			52,384,876
Effect of dilutive options and warrants		1,046,677		—			—

Diluted weighted average common shares outstanding		56,402,479		53,679,134			52,384,876

Diluted earnings (loss) per common share	$	0.09	$	(1.25	)	$	(0.72	)

Basic earnings per common share is calculated using the weighted average shares of Common Stock outstanding during the period. Common equivalent shares from stock options, RSUs, warrants and convertible preferred stock using the treasury stock method, are also included in the diluted per share calculations unless the effect of inclusion would be antidilutive. During the years ended December 31, 2017, 2016 and 2015, outstanding stock options, RSUs, warrants and convertible preferred stock of 6,531,346, 10,228,929 and 9,788,838, respectively, were not included in the computation of diluted earnings per common share, because to do so would have had an antidilutive effect because the outstanding exercise prices were greater than the average market price of the common shares during the relevant periods.

The following is the total outstanding options, RSUs and warrants for the years ended December 31, 2017, 2016 and 2015, respectively.


	2017		2016		2015
Options, RSUs, warrants and convertible preferred stock to purchase Common Stock		9,555,869		10,228,929		9,788,838