v3.20.1

Basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Numerator: |  |
Net income attributable to Atlantic Power Corporation | $ 29.5 | $ 8.9
Add: convertible debenture interest expense | 0.9 | 1.3
Net income (loss) available to common stockholder, Diluted | $ 30.4 | $ 10.2
Denominator: |  |
Weighted average basic shares outstanding | 107.2 | 108.9
Basic earnings per share attributable to Atlantic Power Corporation | $ 0.28 | $ 0.08
Convertible debentures (in shares) | 27.4 | 29.1
Share-based compensation (in shares) | 0.2 | 0.6
Weighted Average Number of Potentially Diluted Shares | 134.8 | 138.6
Diluted earnings per share attributable to Atlantic Power Corporation | $ 0.23 | $ 0.07

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