v2.4.0.8

Employee incentive programs | 9 Months Ended
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Sep. 30, 2013
Employee incentive programs |
Employee incentive programs | 9. Employee incentive programs Long-Term Incentive Program The following table summarizes the changes in LTIP notional units during the nine months ended September 30, 2013:
(Units in thousands) |  | Units |  | Grant Date Weighted-Average Price per Unit |
--- | --- | --- | --- | --- | ---
Outstanding at December 31, 2012 |  |  | 492,535 |  | $ | 13.88 |
Granted |  |  | 597,031 |  |  | 4.91 |
Reinvested |  |  | 45,344 |  |  | 9.12 |
Forfeited |  |  | (138,473 | ) |  | 8.88 |
Vested |  |  | (202,696 | ) |  | 13.48 |
Outstanding at September 30, 2013 |  |  | 793,741 |  | $ | 7.76 |
Certain awards have a market condition based on our total shareholder return during the performance period compared to a group of peer companies and, in some cases, Project Adjusted EBITDA per common share compared to budget. Compensation expense for notional units granted in 2013 is recorded net of estimated forfeitures. See Note 14 to the consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2012 for further details. Cash payments made for vested notional units for the nine months ended September 30, 2013 was $0.9 million. Compensation expense for LTIP was $0.4 million and $1.7 million for the three and nine months end September 30, 2013, respectively. The calculation of simulated total shareholder return under the Monte Carlo model for the remaining time in the performance period for awards with market conditions included the following assumptions as of September 30, 2013 and December 31, 2012:
|  | September 30, 2013 |  | December 31, 2012
--- | --- | --- | --- | ---
Weighted average risk free rate of return |  | 0.0 – 0.5% |  | 0.1 – 0.3%
Dividend yield |  | 9.0% |  | 10.1%
Expected volatility—Atlantic Power |  | 42.2% |  | 22.5%
Expected volatility—peer companies |  | 10.6 – 96.3% |  | 11.9 – 97.1%
Weighted average remaining measurement period |  | 2.1 years |  | 1.4 years

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- Definition The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 50 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6406099&loc=d3e25284-112666 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5444-113901 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 + Details
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