Coverage for Eligible Retirees Under the Age of Sixty-Five. 16.4.3.1 The District’s premium payment for health benefits for a retiree under this section shall be limited to the cost of coverage equivalent to the most expensive Health Maintenance Organization (HMO) plan available to active employees during any particular year. The cost to the retiree is based on the retiree premium rate of the HMO plan in which the retiree is enrolled.