We granted 23,923 and 52,237 restricted stock units (RSUs) during the three months ended June 30, 2022 and 2021, respectively, and granted 677,129 and 376,828 RSUs during the six months ended June 30, 2022 and 2021, respectively. Equity-based compensation expense related to RSUs was $15.5 million and $10.7 million during the three months ended June 30, 2022 and 2021, respectively, and $29.7 million and $20.8 million during the six months ended June 30, 2022 and 2021, respectively.

We present below a summary of changes during the six months ended June 30, 2022 in our unvested units of restricted stock:

	Number of shares/units
Outstanding at December 31, 2021		1,388,467
Granted		677,129
Vested		(570,913	)
Forfeited		(24,073	)
Outstanding at June 30, 2022		1,470,610