Our currently outstanding equity-based awards were issued under our Equity Plan which provides for the granting of stock options, stock appreciation rights, restricted stock, restricted stock units, dividend equivalent rights, and other equity-based awards or incentive awards.

Stock options granted may be either incentive stock options or non-qualified stock options. Vesting terms may vary with each grant, and stock option terms are generally five to ten years. We have outstanding equity-based awards in the form of restricted stock awards. All of our outstanding equity-based awards are classified as equity.

The 235,000 stock options outstanding as of December 31, 2020 expired unexercised on February 13, 2021 and were forfeited.

The following table summarizes time-based restricted stock activity under our Equity Plan for 2021 and 2020:


	Number of Shares	Weighted Average Grant Date Fair Value per Share		Aggregate Current Value
				(in thousands)
Non-vested December 31, 2019	448,467	$	12.51
Granted	299,562	8.47
Vested	(172,170)	13.31
Forfeited	(2,282)	8.64
Non-vested December 31, 2020	573,577	10.18
Granted	536,980	10.27
Vested	(503,914)	10.51
Forfeited	(1,173)	9.98
Non-vested December 31, 2021	605,470	$	9.98	$	5,909

The awards granted to our non-executive employees generally vest over a four-year period based on continuous service (20% on the first, second and third anniversary of the grant date and 40% on the fourth anniversary of the grant date).

The awards granted to our executive officers generally vest over a three-year period based on continuous service (25% on the first and second anniversary of the grant date and 50% on the third anniversary of the grant date) or in certain circumstances upon a change in control.

The holders of these awards have the right to vote the related shares of Common Stock and receive all dividends declared and paid whether or not vested. The fair value of time-based restricted stock awards granted is calculated based on the market value of our Common Stock on the date of grant.

During the years ended December 31, 2021, 2020, and 2019, the total fair value of time-based restricted stock awards that vested was $5.3 million, $2.3 million and $2.0 million, respectively. The total fair value of time-based stock awards that vested during the year ended December 31, 2021 includes $1.5 million of time-based restricted stock for which the vesting was accelerated related to the retirement of our Executive Chairman.

The following table summarizes performance-based restricted stock activity under our Equity Plan for 2021 and 2020:


	Number of Shares	Weighted Average Grant Date Fair Value per Share		Aggregate Current Value
				(in thousands)
Non-vested December 31, 2019	755,991	$	14.31
Granted	376,609	9.38
Vested	—	—
Forfeited	(210,361)	17.13
Non-vested December 31, 2020	922,239	11.65
Granted	323,930	14.05
Vested	(182,480)	13.73
Forfeited	(60,823)	13.73
Non-vested December 31, 2021	1,002,866	$	11.92	$	9,788

Our performance-based restricted stock awards are market-based awards and are accounted for based on the fair value of our Common Stock on the grant date. The fair value of the performance-based restricted stock awards granted was estimated using a Monte Carlo simulation valuation model. These awards generally vest over a three-year period based on our percentile

ranking within the SNL U.S. REIT Hotel Index at the end of the period or upon a change in control. The awards require continued service during the measurement period and are subject to the other conditions described in the Equity Plan or award document.

The number of shares the executive officers may earn under these awards range from zero shares to twice the number of shares granted based on our percentile ranking within the index at the end of the measurement period. In addition, a portion of the performance-based shares may be earned based on the Company's absolute total shareholder return calculated during the performance period.

The holders of these grants have the right to vote the granted shares of Common Stock and any dividends declared will be accumulated and will be subject to the same vesting conditions as the awards. Further, if additional shares are earned based on our percentile ranking within the index, dividend payments will be issued as if the additional shares had been held throughout the measurement period.

The fair value of performance-based restricted stock awards granted was estimated using a Monte Carlo simulation valuation model and the following assumptions:


	2021			2020			2019
Expected dividend yield	—		%	8.16		%	6.17		%
Expected stock price volatility	63.7		%	23.7		%	23.2		%
Risk-free interest rate	0.34		%	0.53		%	2.43		%
Monte Carlo iterations	100,000			100,000			100,000
Weighted average estimated fair value of performance-based restricted stock awards	$	14.05		$	9.38		$	12.81

The expected dividend yield was calculated based on our annual expected dividend payments at the time of grant. The expected volatility was based on historical price changes of our Common Stock for a period comparable to the performance period. The risk-free interest rates were interpolated from the Federal Reserve Bond Equivalent Yield rates for “on-the-run” U.S. Treasury securities.

During the years ended December 31, 2021 and 2020, we granted 60,546 and 93,810 shares of Common Stock, respectively, to our non-employee directors as a part of our director compensation program. These grants were made pursuant to our Equity Plan and were vested upon grant.

Equity-based compensation expense included in Corporate General and Administrative expense in the Consolidated Statements of Operations for the years ended December 31, 2021, 2020, and 2019 was as follows (in thousands):


	2021		2020		2019

Time-based restricted stock	$	4,784	$	2,470	$	2,327
Performance-based restricted stock	5,314		3,559		3,396
Director stock	583		447		496
	$	10,681	$	6,476	$	6,219

We recognize equity-based compensation expense ratably over the vesting terms. The amount of expense may be subject to adjustment in future periods due to a change in the forfeiture assumptions.

Unrecognized equity-based compensation expense for all non-vested awards pursuant to our Equity Plan was $8.0 million at December 31, 2021 as follows (in thousands):


	Total		2022		2023		2024		2025
Time-based restricted stock	$	3,823	$	1,929	$	1,468	$	404	$	22
Performance-based restricted stock	4,153		2,261		1,637		255		—
	$	7,976	$	4,190	$	3,105	$	659	$	22

The Company's former Executive Chairman retired in January 2022. In connection with his retirement, the Company recorded $2.9 million of additional stock-based compensation expense during the year ended December 31, 2021 related to the modification of certain stock award agreements. This amount was comprised of $1.5 million related to time-based restricted stock awards and $1.4 million related to performance-based restricted stock awards.