The calculations of earnings per common share for the quarters and nine-month periods ended September 30, 2021 and 2020 are as follows:

Quarter Ended

Nine-Month Period Ended

September 30,

2021

2020

2021

2020

(In thousands, except per share information)

Net income

$

75,678

$

28,613

$

207,386

$

52,135

Less: Preferred stock dividends

(669)

(2,007)

Net income attributable to common stockholders

$

75,009

$

27,944

$

205,379

$

50,128

Weighted-Average Shares:

Average common shares outstanding

206,725

216,922

212,406

216,876

Average potential dilutive common shares

1,071

793

1,117

657

Average common shares outstanding - assuming dilution

207,796

217,715

213,523

217,533

Earnings per common share:

Basic

$

0.36

$

0.13

$

0.97

$

0.23

Diluted

$

0.36

$

0.13

$

0.96

$

0.23