Earnings Per Common Share

12 Months Ended

Dec. 31, 2019

The following is a reconciliation of the numerators and denominators of the basic and diluted earnings per common share computations in 2019, 2018 and 2017 (in millions, except per share amounts):



	Year Ended December 31,
	2019	2018	2017
Basic:



	Year Ended December 31,
	2019		2018		2017
Net income attributable to Intercontinental Exchange, Inc.	$	1,933	$	1,988	$	2,526
Weighted average common shares outstanding	561		575		589
Basic earnings per common share	$	3.44	$	3.46	$	4.29
Diluted:
Weighted average common shares outstanding	561		575		589
Effect of dilutive securities - stock options and restricted stock	4		4		5
Diluted weighted average common shares outstanding	565		579		594
Diluted earnings per common share	$	3.42	$	3.43	$	4.25

Basic earnings per common share is calculated using the weighted average common shares outstanding during the periods. The weighted average common shares outstanding decreased in 2019 from 2018, and in 2018 from 2017, primarily due to stock repurchases (Note 12).

Common equivalent shares from stock options and restricted stock awards, using the treasury stock method, are included in the diluted per share calculations unless the effect of their inclusion would be antidilutive. During 2019, 2018 and 2017 454,000, 471,000 and 694,000 outstanding stock options, respectively, were not included in the computation of diluted earnings per common share because to do so would have had an antidilutive effect. As of both December 31, 2019 and 2018, there were 89,000 restricted stock units that were vested but have not been issued that are included in the computation of diluted earnings per share. Certain figures in the table above may not recalculate due to rounding.