The following tables present the computation of basic and diluted earnings per common share for the periods indicated:



	Three Months Ended September 30,
(Dollars in millions, except per share amounts)	2015			2014
Net income	$	585		$	560
Less:
Preferred stock dividends	(42		)	(18		)
Dividends and undistributed earnings allocated to participating securities⁽¹⁾	—			—
Net income available to common shareholders	$	543		$	542
Average common shares outstanding (in thousands):
Basic average common shares	406,612			421,974
Effect of dilutive securities: common stock options and common stock awards	5,555			7,762
Diluted average common shares	412,167			429,736
Anti-dilutive securities⁽²⁾	619			876
Earnings per Common Share:
Basic	$	1.34		$	1.28
Diluted⁽³⁾	1.32			1.26



	Nine Months Ended September 30,
(Dollars in millions, except per share amounts)	2015			2014
Net income	$	1,416		$	1,545
Less:
Preferred stock dividends	(102		)	(43		)
Dividends and undistributed earnings allocated to participating securities⁽¹⁾	(1		)	(2		)
Net income available to common shareholders	$	1,313		$	1,500
Average common shares outstanding (in thousands):
Basic average common shares	409,816			426,775
Effect of dilutive securities: common stock options and common stock awards	5,956			7,735
Diluted average common shares	415,772			434,510
Anti-dilutive securities⁽²⁾	675			1,502
Earnings per Common Share:
Basic	$	3.20		$	3.52
Diluted⁽³⁾	3.16			3.45

⁽¹⁾Represents the portion of net income available to common equity allocated to participating securities, composed of fully vested deferred director stock and unvested restricted stock that contain non-forfeitable rights to dividends during the vesting period on a basis equivalent to dividends paid to common shareholders.

⁽²⁾Represents common stock options and other equity-based awards outstanding but not included in the computation of diluted average common shares, because their effect was anti-dilutive.

⁽³⁾Calculations reflect allocation of earnings to participating securities using the two-class method, as this computation is more dilutive than the treasury stock method.