Note 11 - Stock-Based Compensation - Continued Cash-settled RSUs vest over a one to three-year service period, beginning at the date of grant, and the compensation cost is recognized ratably during the vesting period. Forfeitable dividends on cash-settled RSUs are accrued in the form of cash. Compensation cost for cash-settled RSUs subject to accelerated vesting at the date of retirement eligibility is recognized over the implicit service period. The amount payable per unit awarded is equal to the price per share of Unum Group's common stock at settlement of the award, and as such, we measure the value of the award each reporting period based on the current stock price. The effects of changes in the stock price during the service period are recognized as compensation cost over the service period. Changes in the amount of the liability due to stock price changes after the service period are recognized as compensation cost during the period in which the changes occur. At December 31, 2020, we had $1.1 million of unrecognized compensation cost related to cash-settled RSUs that will be recognized over a weighted average period of 1.1 years. The cash-settled RSUs have a weighted average grant date fair value per unit granted of $22.94. As of December 31, 2020, no amount of cash- settled RSUs have vested or been paid. Stock Options Stock option activity is summarized as follows: Remaining Intrinsic Shares Weighted Average Contractual Term Value (000s) Exercise Price (in years) (in millions) Outstanding at December 31, 2019 74  $ 24.09  Exercised (13) 23.35  Forfeited (21) 24.25  Outstanding at December 31, 2020 40  24.25  0.1 $ —  Exercisable at December 31, 2020 40  $ 24.25  0.1 $ —  All outstanding stock options at December 31, 2020 have vested. Stock options vest over a one to three-year service period, beginning at the date of grant, and the compensation cost is recognized ratably during the vesting period. Compensation cost for stock options subject to accelerated vesting at the date of retirement eligibility is recognized over the implicit service period. At December 31, 2020, we had no unrecognized compensation cost related to stock options. The intrinsic value of options exercised in 2020, 2019, and 2018 was $0.1 million, $0.3 million, and $0.7 million, respectively. There were no stock options granted or vested in the years 2018 through 2020. 194 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued Unum Group and Subsidiaries