v2.4.0.6

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

3 Months Ended

Mar. 31, 2013

Basic and diluted earnings (loss) per share

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

		Three months ended March 31,
		2013			2012
Numerator:
Income (loss) from continuing operations attributable to Atlantic Power Corporation		$	5.6		$	(53.9	)
Income from discontinued operations, net of tax			0.9			11.6
Net loss attributable to Atlantic Power Corporation		$	6.5		$	(42.3	)
Denominator:
Weighted average basic shares outstanding			119.5			113.6
Dilutive potential shares:
Convertible debentures			27.7			13.3
LTIP notional units			0.4			0.5
Potentially dilutive shares			147.6			127.4
Diluted loss per share from continuing operations attributable to Atlantic Power Corporation		$	0.04		$	(0.47	)
Diluted earnings per share from discontinued operations			0.01			0.10
Diluted loss per share attributable to Atlantic Power Corporation		$	0.05		$	(0.37	)

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- Definition

Tabular disclosure of the numerators and the denominators of the basic and diluted per-share (or per-unit) computations for income from continuing operations, including the effect that has been given to preferred dividends.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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