Vesting. The Units and all related Dividend Equivalents shall not be delivered to the Employee and may not be sold, assigned, transferred, pledged or otherwise encumbered by the Employee until such Units have vested based on achievement of the performance goals set forth in [Schedule A] and subject to the terms of this Agreement. Any Units earned based on achievement of the specific performance goals shall vest when the Committee certifies the payout level as a result of such performance achievement, and the Shares representing such vested Units shall be paid to the Employee no later than 90 days following the end of the performance period.