v2.4.0.6

Employee incentive programs (Tables)

3 Months Ended

Mar. 31, 2013

Employee incentive programs

Schedule of changes in LTIP notional shares

(Units in thousands)		Units			Grant Date Weighted-Average Price per Unit
Outstanding at December 31, 2012			492,535		$	13.9
Granted			482,384			4.9
Additional units from dividends			9,906			13.8
Forfeited			(42,000	)		12.3
Vested			(200,697	)		13.6
Outstanding at March 31, 2013			742,128		$	8.2

Schedule of assumptions for calculation of simulated total shareholder return under the Monte Carlo model

		March 31, 2013			December 31, 2012
Weighted average risk free rate of return			0.1%			0.1 – 0.3%
Dividend yield			8.0%			10.1%
Expected volatility—Atlantic Power			48.6%			22.5%
Expected volatility—peer companies			11.9 – 72.8%			11.9 – 97.1%
Weighted average remaining measurement period			0.9 years			1.4 years

X

- Definition

Tabular disclosure of the significant assumptions used during the year to estimate the fair value of equity-based payment instruments, excluding stock (or unit) options, including, but not limited to: (a) expected term of equity instruments, (b) expected volatility of the entity's shares and peer entities, (c) expected dividends, (d) risk-free rate(s).

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- Definition

Tabular disclosure of share-based compensation plans that may be presented in a single table for outstanding, vested and expected to vest, and exercisable awards. The information that may be disclosed in this table may include, but is not limited to, number of shares, weighted average exercise price, weighted average remaining contractual life, and aggregate intrinsic value.

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