At June 30, 2024 and December 31, 2023, 9,414,568 and 10,211,459 shares of common stock, respectively, were available for grant under our Incentive Plan. The unamortized compensation cost of awards issued under the Incentive Plan, which are settled by delivery of shares of common stock, and purchases under the Employee Stock Purchase Plan, totaled $36 million at June 30, 2024, as shown in the following table.


	Six Months Ended June 30, 2024
(In Thousands)	Restricted Stock Units		Deferred Stock Units		Performance Stock Units		Employee Stock Purchase Plan		Total
Unrecognized compensations cost at beginning of period	$	3,166	$	18,920	$	15,519	$	—	$	37,605
Equity grants	3,522		7,790		—		266		11,578
Grant date fair value adjustment	—		—		—		—		—
Equity grant forfeitures	(607)		(1,147)		—		—		(1,754)
Equity compensation expense	(1,194)		(6,256)		(3,570)		(134)		(11,154)
Unrecognized Compensation Cost at End of Period	$	4,887	$	19,307	$	11,949	$	132	$	36,275

At June 30, 2024, the weighted average amortization period remaining for all of our equity awards was less than two years.

We generally grant RSUs annually, as part of our compensation process. In addition, RSUs are granted from time to time in connection with hiring and promotions. RSUs generally vest over the course of a four-year vesting period, and are distributed annually, at the end of each vesting period.

At June 30, 2024 and December 31, 2023, we had 791,439 and 593,570 RSUs outstanding, respectively. During the six months ended June 30, 2024, we granted 542,719 RSUs, distributed 271,010 RSUs, and 73,840 RSUs were forfeited due to employee termination. Unvested RSUs at June 30, 2024 vest through 2028.

We generally grant DSUs annually, as part of our compensation process. In addition, DSUs are granted from time to time in connection with hiring and promotions and in lieu of the payment in cash of a portion of annual bonus earned. DSUs generally vest over the course of a four-year vesting period, and are distributed after the end of the final vesting period or after an employee is terminated.

At June 30, 2024 and December 31, 2023, we had 5,576,627 and 4,821,172 DSUs outstanding, respectively, of which 2,603,607 and 2,284,480, respectively, had vested. During the six months ended June 30, 2024, we granted 1,245,295 DSUs, distributed 378,125 DSUs and 111,715 DSUs were forfeited due to employee termination. Unvested DSUs at June 30, 2024 vest through 2028.

We generally grant PSUs annually, as part of our compensation process. PSUs generally have performance-based vesting over the course of a three-year vesting/performance period, and, subject to meeting certain performance criteria, will vest and be distributed after the end of the vesting period.

At June 30, 2024 and December 31, 2023, the target number of PSUs that were unvested was 2,598,194 and 3,072,039, respectively. Vesting for PSUs generally occurs approximately three years from their respective grant dates based on various total shareholder return performance calculations, as discussed in Note 19 to the Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2023.

For 473,845 target PSU awards that were granted in December 2020, the performance vesting period ended on January 1, 2024. Based upon the performance-based vesting criteria of these awards, 564,975 shares of our common stock underlying these PSUs qualified for vesting, which was approved by our Board of Directors during the six months ended June 30, 2024. These PSUs were distributed as shares of our common stock in April 2024.

The ESPP allows a maximum of 1,100,000 shares of common stock to be purchased in aggregate for all employees. As of June 30, 2024 and December 31, 2023, 805,906 and 763,369 shares had been purchased, respectively, and there remained a negligible amount of uninvested employee contributions in the ESPP at June 30, 2024.