For the three months ended September 30, 2020 and 2019, the Company recognized $7.8 million and $7.0 million of stock-based compensation, respectively, that was related to restricted stock units (RSUs). The stock-based compensation was included in indirect costs and selling expenses in the consolidated statements of operations.

During the periods presented all equity instrument grants were made in the form of RSUs. Other than performance-based RSUs (PRSUs) which contain a market-based element, the fair value of RSU grants was determined based on the closing price of a share of the Company’s common stock on the date of grant. The fair value of RSUs with market-based vesting features was also measured on the grant date, but was done so using a binomial lattice model.

The Company granted performance-based stock awards to key employees in October of 2019, October of 2018 and September of 2017. The final number of PRSUs that are earned by participants and vest is based on the achievement of a specified EPS for the fiscal year and on the average share price for the 90-day period ended for the following three years. If the 90-day average share price of the Company’s stock in years one, two and three exceeds the 90-day average share price at the grant date by 100 percent or more the number of shares ultimately awarded could range up to 200 percent of the specified target award. In addition to the performance and market conditions, there is a service vesting condition that stipulates 50 percent of the award will vest approximately three years from the grant date and 50 percent will vest approximately four years from the grant date, depending on the award date. During the second quarter of FY2021, the Company granted its annual performance-based stock awards to key employees.

The annual performance-based awards granted for each of the fiscal years presented were as follows:

	Performance-based stock awards granted		Number of additional shares earned under performance-based stock awards
Fiscal year 2021		7,059		—
Fiscal year 2020		108,844		—
Fiscal year 2019		129,108		12,462

The total number of shares authorized by shareholders for grants under the 2016 Plan and its predecessor plan is 1,200,000 plus any forfeitures from the 2006 Plan. The aggregate number of grants that may be made may exceed this approved amount as forfeited RSUs become available for future grants. As of September 30, 2020, cumulative grants of 937,934 equity instruments underlying the shares authorized have been awarded, and 197,997 of these instruments have been forfeited.

Activity related to RSUs during the three months ended September 30, 2020 is as follows:

	RSUs
Unvested at June 30, 2020		501,923
Granted		73,504
Vested		(17,578	)
Forfeited		(10,286	)
Unvested at September 30, 2020		547,563

As of September 30, 2020, there was $35.4 million of total unrecognized compensation costs related to RSUs scheduled to be recognized over a weighted-average period of 2.3 years.