9. SHARE-BASED COMPENSATION

Performance-Based Shares. The Company issued a total of 36,849 performance-based shares to three of the Company’s executives during the first quarter of 2022. The vesting for these performance-based shares is based on the compounded annual growth rate of the Company’s Adjusted EBITDA and Free Cash Flow Per Share, as defined, for the three-year periods ending December 31, 2022, December 31, 2023, and December 31, 2024. For the 2022 period, one-sixth of such performance-based shares will vest on the anniversary date of the award if the Company’s annual Adjusted EBITDA for 2022 reflects at least 10% per annum growth since 2019, and one-sixth of such performance-based shares will vest on the anniversary date if the Company’s annual Free Cash Flow Per Share for 2022 reflects at least 12% per annum growth since 2019. Vesting of the performance-based shares is similar for the 2023 and 2024 periods.

On March 14, 2022, the Company issued 23,325 shares of stock to one of the Company’s executives for having previously met performance-based metrics in 2021 pertaining to Adjusted EBITDA growth and Free Cash Flow Per Share growth.

As of March 31, 2022, the Company had 1,561,690 share-based awards authorized by shareholders and available for grant from the Company’s 2015 Equity Incentive Plan.

The following table summarizes information related to the Company’s common stock options as of March 31, 2022:

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Components of compensation expense are as follows:

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As of March 31, 2022, there was approximately $2.1 million of unrecognized compensation cost related to unvested stock options previously granted that is expected to be recognized over a weighted-average period of approximately 2.3 years. As of such date, there was also $0.7 million of unrecognized compensation cost related to unvested restricted and performance shares, which is expected to be recognized over a weighted-average period of 1.6 years.