We issue service-based restricted stock units (“Service RSUs”), service and performance-based restricted stock units (“Performance RSUs”) and nonqualified stock options (“Options”) to certain employees and directors. We recognized share-based compensation expense of $4 million for the three months ended March 31, 2021. For the three months ended March, 31, 2020, we recognized a credit to share-based compensation expense of $2 million due to the reversal of $8 million of expense recognized in prior years related to our Performance RSUs which were not expected to achieve certain performance targets. As of March 31, 2021, unrecognized compensation costs for unvested awards were approximately $49 million, which is expected to be recognized over a weighted average period of 1.6 years. As of March 31, 2021, there were 4,024,218 shares of common stock available for future issuance under this plan.

During the three months ended March 31, 2021, we issued 560,604 Service RSUs with a grant date fair value of $38.22, which generally vest in equal annual installments over three years from the date of grant.

During the three months ended March 31, 2021, we issued 542,793 Options with an exercise price of $38.22, which vest over three years from the date of the grant.

The weighted-average grant date fair value of these options was $13.30, which was determined using the Black-Scholes-Merton option-pricing model with the following assumptions:

Expected volatility	34.2	%
Dividend yield	—	%
Risk-free rate	1.1	%
Expected term (in years)	6.0

As of March 31, 2021, we had 1,416,603 Options outstanding that were exercisable.

During the three months ended March 31, 2021, we issued 124,711 Performance RSUs with a grant date fair value of $38.22. The Performance RSUs are settled at the end of a three-year performance period, with 50 percent of the Performance RSUs subject to achievement based on the Company’s adjusted earnings before interest expense, taxes and depreciation and amortization further adjusted for net deferral and recognition of revenues and related direct expenses related to sales of VOIs of projects under construction. The remaining 50 percent of the Performance RSUs are subject to the achievement of certain contract sales targets. We determined that the performance conditions for these awards are probable of achievement and, as of March 31, 2021, we recognized compensation expense based on the number of Performance RSUs we expect to vest.

In March 2017, the Board of Directors adopted the Hilton Grand Vacations Inc. Employee Stock Purchase Plan (the “ESPP”), which became effective during 2017. In connection with the Plan, we issued 2.5 million shares of common stock which may be purchased under the ESPP. The ESPP allows eligible employees to purchase shares of our common stock at a price per share not less than 95 percent of the fair market value per share of common stock on the purchase date, up to a maximum threshold established by the plan administrator for the offering period. During the three months ended March 31, 2021 and 2020, we recognized less than $1 million of compensation expense related to this plan.