7. Earnings per common share

The computations of basic earnings per common share follow:

	Three Months Ended September 30						Nine Months Ended September 30
	2018			2017			2018			2017
	(In thousands, except per share)

Income available to common shareholders:
Net income	$	526,091			355,923			1,371,861			1,085,903
Less: Preferred stock dividends (a)		(18,130	)		(18,130	)		(54,390	)		(54,604	)
Net income available to common equity		507,961			337,793			1,317,471			1,031,299
Less: Income attributable to unvested stock-based compensation awards		(2,598	)		(1,992	)		(6,774	)		(6,288	)
Net income available to common shareholders	$	505,363			335,801			1,310,697			1,025,011
Weighted-average shares outstanding:
Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards		143,556			152,245			146,177			153,814
Less: Unvested stock-based compensation awards		(734	)		(898	)		(753	)		(948	)
Weighted-average shares outstanding		142,822			151,347			145,424			152,866

Basic earnings per common share	$	3.54			2.22			9.01			6.71

(a)Including impact of not as yet declared cumulative dividends.

The computations of diluted earnings per common share follow:

	Three Months Ended September 30						Nine Months Ended September 30
	2018			2017			2018			2017
	(In thousands, except per share)

Net income available to common equity	$	507,961			337,793			1,317,471			1,031,299
Less: Income attributable to unvested stock-based compensation awards		(2,596	)		(1,989	)		(6,768	)		(6,276	)
Net income available to common shareholders	$	505,365			335,804			1,310,703			1,025,023
Adjusted weighted-average shares outstanding:
Common and unvested stock-based compensation awards		143,556			152,245			146,177			153,814
Less: Unvested stock-based compensation awards		(734	)		(898	)		(753	)		(948	)
Plus: Incremental shares from assumed conversion of stock-based compensation awards and warrants to purchase common stock		154			344			181			427
Adjusted weighted-average shares outstanding		142,976			151,691			145,605			153,293

Diluted earnings per common share	$	3.53			2.21			9.00			6.69

GAAP defines unvested share-based awards that contain nonforfeitable rights to dividends or dividend equivalents (whether paid or unpaid) as participating securities that shall be included in the computation of earnings per common share pursuant to the two-class method. The Company has issued stock-based compensation awards in the form of restricted stock and restricted stock units which, in accordance with GAAP, are considered participating securities.

Stock-based compensation awards and warrants to purchase common stock of M&T representing 212,407 and 408,657 common shares during the three-month periods ended September 30, 2018 and 2017, respectively, and 220,653 and 404,487 common shares during the nine-month periods ended September 30, 2018 and 2017, respectively, were not included in the computations of diluted earnings per common share because the effect on those periods would have been antidilutive.