Total stock-based compensation was $485 and $480 for the three months ended September 30, 2020 and 2019, respectively and $578 and $754 for the nine months ended September 30, 2020 and 2019, respectively. As of September 30, 2020, there was $1,242 of unearned compensation expense related to restricted stock awards, which will be recognized over the remaining weighed average requisite service period of 20 months. As of September 30, 2020, there was $252 of unearned compensation related to time-vested stock options, which will be recognized over the remaining requisite service period of 15 months.

During the nine months ended September 30, 2020, the Company granted 1,139,464 cash settled stock appreciation rights to certain employees of which 305,121 were forfeited during 2020 and 834,343 remain outstanding as of September 30, 2020. Each stock appreciation right represents the right to receive a payment measured by the increase in the fair market value of one share of the Company’s stock from the date of grant of the stock appreciation right to the date of exercise of the stock appreciation right. The cash settled stock appreciation rights vest ratably over three years and have a contractual life of 10 years. Cash settled stock appreciation rights are classified as liabilities. The Company measures the fair value of cash settled stock appreciation rights using the Black-Scholes option valuation model and remeasures the fair value of the award each reporting period until the award is settled. Compensation cost for cash settled stock appreciation rights is trued up each reporting period for changes in fair value pro-rated for the portion of the requisite service period rendered. Once vested the Company immediately recognizes compensation cost for any changes in fair value of cash settled stock appreciation rights until settlement. The estimated fair value of the cash settled stock appreciation rights as of September 30, 2020 was $1,135. Stock-based compensation for cash settled stock appreciation rights was $261 and $192 for the three and nine months ended September 30, 2020.

The fair value of cash settled stock appreciation rights as of September 30, 2020 was estimated using the Black-Scholes option valuation model with the following assumptions:


				Expected	Risk Free
			Expected	Dividend	Interest	Fair Value
Grant Year	Grant Date	Expected Life	Volatility	Yield	Rate	Per Award

2020	1/24/2020	5.3 years	61.00%	0.00%	0.31%	$1.36
2020	3/9/2020	5.4 years	60.75%	0.00%	0.32%	$1.45
2020	9/14/2020	6.0 years	59.76%	0.00%	0.36%	$1.28