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



	Three Months Ended June 30,
(Dollars in millions, except per share amounts)	2017			2016
Net income	$	620		$	619
Less:
Preferred stock dividends	(36		)	(33		)
Dividends and undistributed earnings allocated to participating securities⁽¹⁾	—			(1		)
Net income available to common shareholders	$	584		$	585
Average common shares outstanding (In thousands):
Basic average common shares	375,395			394,160
Effect of dilutive securities: equity-based awards	5,520			4,687
Diluted average common shares	380,915			398,847
Anti-dilutive securities⁽²⁾	293			3,277
Earnings per Common Share:
Basic	$	1.56		$	1.48
Diluted⁽³⁾	1.53			1.47

	Six Months Ended June 30,
(Dollars in millions, except per share amounts)	2017			2016
Net income	$	1,122		$	987
Less:
Preferred stock dividends	(91		)	(82		)
Dividends and undistributed earnings allocated to participating securities⁽¹⁾	(1		)	(1		)
Net income available to common shareholders	$	1,030		$	904
Average common shares outstanding (In thousands):
Basic average common shares	378,293			396,790
Effect of dilutive securities: equity-based awards	5,196			4,323
Diluted average common shares	383,489			401,113
Anti-dilutive securities⁽²⁾	527			3,426
Earnings per Common Share:
Basic	$	2.72		$	2.28
Diluted⁽³⁾	2.69			2.25

⁽¹⁾Represents the portion of net income available to common equity allocated to participating securities, composed of unvested and fully vested SERP shares and fully vested deferred director stock awards, which are equity-based awards that contain non-forfeitable rights to dividends, and are considered to participate with the common stock in undistributed earnings.

⁽²⁾Represents equity-based awards outstanding but not included in the computation of diluted average common shares, because their effect was anti-dilutive. Additional information about equity-based awards is provided in Note 18 to the consolidated financial statements included under Item 8, Financial Statements and Supplementary Data, in our 2016 Form 10-K.

⁽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.