Earnings Per Share and Equity (Exelon and BGE)

12 Months Ended

Dec. 31, 2016

Earnings Per Share and Equity (Exelon and BGE)

(Exelon)

Diluted earnings per share is calculated by dividing Net income attributable to common shareholders by the weighted average number of shares of common stock outstanding, including shares to be issued upon exercise of stock options, performance share awards and restricted stock outstanding under Exelon’s LTIPs considered to be common stock equivalents. The following table sets forth the components of basic and diluted earnings per share and shows the effect of the stock options, performance share awards and restricted stock on the weighted average number of shares outstanding used in calculating diluted earnings per share:



	Years Ended December 31,
	2016		2015		2014
Net income attributable to common shareholders	$	1,134	$	2,269	$	1,623
Weighted average common shares outstanding—basic	924		890		860
Assumed exercise and/or distributions of stock-based awards	3		3		4
Weighted average common shares outstanding—diluted	927		893		864

The number of stock options not included in the calculation of diluted common shares outstanding due to their antidilutive effect was approximately 12 million in 2016, 16 million in 2015, and 17 million in 2014. There were no equity units related to the PHI merger not included in the calculation of diluted common shares outstanding due to their antidilutive effect for the year ended December 31, 2016. The number of equity units related to the PHI merger not included in the calculation of diluted common shares outstanding due to their antidilutive effect were 3 million and less than 1 million for the years ended December 31, 2015 and 2014. Refer to Note 20 — Shareholders' Equity for further information regarding the equity units and equity forward units.

Under share repurchase programs, 35 million shares of common stock are held as treasury stock with a cost of $2.3 billion as of December 31, 2016. In 2008, Exelon management decided to defer indefinitely any share repurchases.