EARNINGS PER SHARE

Earnings per share is calculated based on income from continuing and discontinued operations less any income attributable to noncontrolling interests. Income attributable to noncontrolling interests represents third-party limited partner unitholders' interests in the earnings of our consolidated subsidiary, Rose Rock. Rose Rock allocates net income to its limited partners based on the distributions pertaining to the current period's available cash as defined by Rose Rock's partnership agreement. After adjusting for the appropriate period's distributions, the remaining undistributed earnings or excess distributions over earnings, if any, are allocated to Rose Rock's general partner, limited partners and participating securities in accordance with the contractual terms of Rose Rock's partnership agreement and as further prescribed under the two-class method. Incentive distribution rights do not participate in undistributed earnings.

Basic earnings (loss) per share is calculated based on the weighted average shares outstanding during the period. Diluted earnings (loss) per share includes the dilutive effect of warrants and unvested equity compensation awards.

The following summarizes the calculation of basic earnings per share for the years ended December 31, 2015, 2014 and 2013 (in thousands, except per share amounts):



	Year Ended December 31, 2015
	Continuing Operations		Discontinued Operations			Net
Income	$	42,816	$	(4	)	$	42,812
less: Income attributable to noncontrolling interest	12,492		—			12,492
Income attributable to SemGroup	$	30,324	$	(4	)	$	30,320
Weighted average common stock outstanding	43,787		43,787			43,787
Basic earnings per share	$	0.69	$	0.00		$	0.69



	Year Ended December 31, 2014
	Continuing Operations		Discontinued Operations			Net
Income	$	52,058	$	(1	)	$	52,057
less: Income attributable to noncontrolling interest	22,817		—			22,817
Income attributable to SemGroup	$	29,241	$	(1	)	$	29,240
Weighted average common stock outstanding	42,665		42,665			42,665
Basic earnings per share	$	0.69	$	0.00		$	0.69



	Year Ended December 31, 2013
	Continuing Operations		Discontinued Operations		Net
Income	$	65,753	$	59	$	65,812
less: Income attributable to noncontrolling interest	17,710		—		17,710
Income attributable to SemGroup	$	48,043	$	59	$	48,102
Weighted average common stock outstanding	42,339		42,339		42,339
Basic earnings per share	$	1.13	$	0.00	$	1.14

The following summarizes the calculation of diluted earnings per share for the years ended December 31, 2015, 2014 and 2013 (in thousands, except per share amounts):



	Year Ended December 31, 2015
	Continuing Operations		Discontinued Operations			Net
Income	$	42,816	$	(4	)	$	42,812
less: Income attributable to noncontrolling interest	12,492		—			12,492
Income attributable to SemGroup	$	30,324	$	(4	)	$	30,320
Weighted average common stock outstanding	43,787		43,787			43,787
Effect of dilutive securities	183		183			183
Diluted weighted average common stock outstanding	43,970		43,970			43,970
Diluted earnings per share	$	0.69	$	0.00		$	0.69



	Year Ended December 31, 2014
	Continuing Operations		Discontinued Operations			Net
Income	$	52,058	$	(1	)	$	52,057
less: Income attributable to noncontrolling interest	22,817		—			22,817
Income attributable to SemGroup	$	29,241	$	(1	)	$	29,240
Weighted average common stock outstanding	42,665		42,665			42,665
Effect of dilutive securities	302		302			302
Diluted weighted average common stock outstanding	42,967		42,967			42,967
Diluted earnings per share	$	0.68	$	0.00		$	0.68



	Year Ended December 31, 2013
	Continuing Operations		Discontinued Operations		Net
Income	$	65,753	$	59	$	65,812
less: Income attributable to noncontrolling interest	17,710		—		17,710
Income attributable to SemGroup	$	48,043	$	59	$	48,102
Weighted average common stock outstanding	42,339		42,339		42,339
Effect of dilutive securities	307		307		307
Diluted weighted average common stock outstanding	42,646		42,646		42,646
Diluted earnings per share	$	1.13	$	0.00	$	1.13

All outstanding warrants expired on November 30, 2014 and therefore have no dilutive effect for the years ended December 31, 2015 and 2014. For the year ended December 31, 2013, we recorded a loss on the change in the fair value of the warrants; because of this, the warrants did not cause any dilution for that period.