The Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (MMA) added prescription drug coverage to Medicare (Medicare Part D), beginning on January 1, 2006. Medicare beneficiaries can obtain the Medicare drug benefit through two types of private plans: a stand-alone prescription drug plan (PDP) for beneficiaries in the traditional fee-for-service program or a Medicare Advantage (MA) plan, such as an HMO or PPO, that covers prescription drugs.
Data have been rounded and may not sum to total. United States totals include data for beneficiaries residing in the territories, as well as those with unknown states of residence.
Source: The Henry J Kaiser Family Foundation, K.F.F. (2016). KFF.org. Retrieved 13 May, 2016.