our investors’ interests, the performance award also contains opportunities to earn an additional 50% of the target units based on achievement of un-levered pre-tax free cash flow targets and an additional 50% of the target units based on leverage ratio reduction targets. The total number of potential performance units that may be earned over the extended period will thus range from 0% to 300% of the target number of units. In order to retain and motivate over a longer period, performance will be measured starting in 2023, and the performance period is January 1, 2021 – December 31, 2025.
Performance against the Adjusted EBITDA portion of the award will be measured for each of 2023, 2024 and 2025 and will be based on performance against functional currency Adjusted EBITDA targets for each year that become incrementally higher each year. Payouts of the Adjusted EBITDA portion of the award will be based on the same scale as our 2020-2022 performance awards. Units under the Adjusted EBITDA portion of the award vest as they are earned starting with 2023 and become payable shortly after the end of the calendar year in which units are earned, subject to the executive remaining in continuous employment through the payment date except for certain qualifying terminations. To earn units under the Adjusted EBITDA portion of the award in calendar years 2024 and 2025, the calculated payout must be incrementally higher than the prior year(s) and the units earned in those years will be limited to the incremental difference, if any.
Performance against the un-levered pre-tax free cash flow and leverage ratio goals will be measured for each of 2023, 2024 and 2025, and the targets become incrementally more challenging each year. Each of these goals will be determined to have been achieved or not achieved for such year (with no interpolation for performance or payout). Payout for each of these metrics will be at 0% or 50% of the target number of potential performance units. Units under the un-levered pre-tax free cash flow and leverage ratio portions of the award can vest and be paid starting in 2025 (if goals are achieved in 2023 or 2024) subject to the executive remaining in continuous employment through the payment date and subject to certain qualifying terminations. Units earned in calendar year 2025 under these components will be payable shortly after the end of calendar year 2025 provided the executive remains in continuous employment through the payment date, except for certain qualifying terminations.
The target numbers of units for the named executive officers’ 2021-2025 performance unit awards are as follows: Mr. Zimmerman (50,147), Mr. Witherow (13,451), Mr. Fisher (15,171), Mr. Milkie (9,014) and Ms. Semmelroth (7,623). The numbers of restricted units awarded to each of our named executive officers are as follows: Mr. Zimmerman (21,492), Mr. Witherow (8,968), Mr. Fisher (10,114), Mr. Milkie (6,009), and Ms. Semmelroth (5,082). The double-trigger change in control provisions of the 2016 Omnibus Incentive Plan apply to these performance unit and restricted unit awards. The Form of Performance Unit Award Agreement and Restricted Unit Award Declaration are filed as exhibits to this Current Report on Form 8-K, and the above summary is qualified in its entirety by reference to such exhibits.
