Three Months Ended September 30,

Nine Months Ended September 30,

(In millions except per share data)

2020

2019

2020

2019

Net income (loss)

$

177.4

$

250.9

$

(228.5)

$

398.2

Average common shares outstanding:

Basic average common shares outstanding

200.1

200.2

200.1

Effect of dilutive securities:

Contingently issuable shares (performance and restricted stock units)

0.3

0.6

—

0.5

Diluted average common shares outstanding

200.4

200.8

200.1

200.6

Basic earnings (loss) per average common share

$

0.89

$

1.25

$

(1.14)

$

1.99

Diluted earnings (loss) per average common share

$

0.89

$

1.25

$

(1.14)

$

1.98

Anti-dilutive shares excluded from earnings per share calculation

—

0.3

—