Basic and diluted (loss) earnings per share (Tables)

6 Months Ended

Jun. 30, 2020

Basic and diluted (loss) earnings per share

Schedule of diluted net income and potentially dilutive shares utilized in the per share calculation

	Three Months Ended June 30,				Six Months Ended June 30,
Basic	2020		2019		2020		2019
Numerator:
Net (loss) income attributable to Atlantic Power Corporation	$	(5.7)	$	1.2	$	23.8	$	10.1
Denominator:
Weighted average basic shares outstanding		97.6		109.7		102.4		109.3
Basic (loss) earnings per share attributable to Atlantic Power Corporation	$	(0.06)	$	0.01	$	0.23	$	0.09
Diluted
Numerator:
Net (loss) income attributable to Atlantic Power Corporation	$	(5.7)	$	1.2	$	23.8	$	10.1
Add: convertible debenture interest expense		—		—		1.9		2.2
		(5.7)		1.2		25.7		12.3
Denominator:
Weighted average basic shares outstanding		97.6		109.7		102.4		109.3
Share-based compensation		—		0.5		0.5		0.5
Convertible debentures		—		—		27.4		28.2
		97.6		110.2		130.3		138.0
Diluted (loss) earnings per share attributable to Atlantic Power Corporation	$	(0.06)	$	0.01	$	0.20	$	0.09

Summary of outstanding instruments that are anti-dilutive and not included in the computation of our diluted (loss) earnings per share

	Three Months Ended June 30,				Six Months Ended June 30,
	2020		2019		2020		2019
Share-based compensation		0.5		—		—		—
Convertible debentures		27.4		27.4		—		—
Total		27.9		27.4		—		—