On July 28, 2015, SunEdison began recognizing expense related to 199,239 performance-based RSUs granted by the Company to certain employees of First Wind in connection with its acquisition by SunEdison on January 29, 2015. The performance-based awards were issued in three tranches covering the 2015, 2016, and 2017 fiscal year performance periods and are based on the achievement of targets related to additions to SunEdison's renewable energy generation project development pipeline and backlog, the volume of renewable energy generation projects transferred into the Company or SunEdison's warehouse vehicles, and the achievement of cash available for distribution by wind power plants sold to the Company through the First Wind Acquisition agreement. The grant-date fair value of these awards was $6.2 million which will be recognized as compensation expense on a straight-line basis over the requisite service periods of one year for the 2015 tranche, two years for the 2016 tranche, and three years for the 2017 tranche. The grant-date fair value of these awards was calculated based on the Company's stock price on the date of grant since meeting the requisite performance conditions was considered probable as of this date. As the achievement of these performance metrics was not considered probable as of the first quarter of 2016, all previously recognized compensation expense for the tranches covering 2015 and 2016 was reversed during the first quarter of 2016 and there are no remaining unvested shares as of December 31, 2016.
The following table presents information regarding outstanding stock options as of December 31, 2016 and changes during the year then ended:
Number of Stock Options Outstanding
Weighted Average Exercise Price Per Share
Balance as of January 1, 2016
Balance as of December 31, 2016
As of December 31, 2016 and 2015, there was no unrecognized compensation cost in relation to outstanding stock options.
As discussed in Note 1. Nature of Operations and Basis of Presentation, on March 6, 2017, TerraForm Power entered into the Merger Agreement with affiliates of Brookfield. Pursuant to the TerraForm Power 2014 Second Amended and Restated Long-Term Incentive Plan, if the Merger is consummated, it will result in a change of control and all outstanding equity awards (RSAs and RSUs) will vest, which would result in a significant stock-based compensation charge in such period. As of December 31, 2016, the Company had $15.2 million of unrecognized compensation expense related to outstanding equity awards.
17. LOSS PER SHARE
Loss per share is based upon the weighted average shares outstanding. Net loss attributable to Class A common stockholders is reduced by the amount of deemed dividends related to the accretion of redeemable non-controlling interest and the amount of dividends paid on Class A shares and participating RSAs. Unvested RSAs that contain non-forfeitable rights to dividends are treated as participating securities and are included in the loss per share computation using the two-class method, to the extent that there are undistributed earnings available as such securities do not participate in losses.