v2.4.0.6

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

12 Months Ended

Dec. 31, 2012

Basic and diluted earnings (loss) per share

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

The following table sets forth the diluted net income and potentially dilutive shares utilized in the per share calculation for the years ended December 31, 2012, 2011 and 2010:

		2012			2011			2010
Numerator:
Loss from continuing operations attributable to Atlantic Power Corporation		$	(129,235	)	$	(74,585	)	$	(27,879	)
Income from discontinued operations, net of tax			16,459			36,177			24,127
Net loss attributable to Atlantic Power Corporation		$	(112,776	)	$	(38,408	)	$	(3,752	)
Denominator:
Weighted average basic shares outstanding			116,426			77,466			61,706
Dilutive potential shares:
Convertible debentures			17,353			13,962			12,339
LTIP notional units			489			438			542
Potentially dilutive shares			134,268			91,866			74,587
Diluted loss per share from continuing operations attributable to Atlantic Power Corporation		$	(1.11	)	$	(0.96	)	$	(0.45	)
Diluted earnings per share from discontinued operations			0.14			0.46			0.39
Diluted loss per share attributable to Atlantic Power Corporation		$	(0.97	)	$	(0.50	)	$	(0.06	)

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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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