Diluted earnings per share is calculated by dividing net income 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 these stock options, performance share awards and restricted stock on the weighted average number of shares outstanding (in millions) used in calculating diluted earnings per share:

	Three Months Ended March 31,
	2013		2012
Net (loss) income	$	(4)	$	200

Weighted average common shares outstanding - basic		855		705
Assumed exercise and/or distributions of stock based awards		-		2

Weighted average common shares outstanding - diluted		855		707

For the three months ended March 31, 2013 in which there was a net loss to common stockholders, no potentially dilutive securities are included in the calculation of diluted loss per share, as inclusion of these securities would have reduced the net loss per share. For the three months ended March 31, 2012, the number of stock options not included in the calculation of diluted common shares outstanding due to their antidilutive effect was approximately 11 million.

Under share repurchase programs, 35 million shares of common stock are held as treasury stock with a cost of $2.327 billion as of March 31, 2013. In 2008, Exelon management decided to defer indefinitely any share repurchases.

PECO has $87 million of cumulative preferred securities that are redeemable at its option at any time for the redemption price established when each series of securities were issued. On March 25, 2013, PECO issued a notice of redemption for all outstanding series of preferred securities with a redemption date of May 1, 2013. The redemption premium will be reflected as a direct charge to retained earnings in PECO's Consolidated Balance Sheet in the second quarter of 2013.