Data as of February 1, 2009.

Residence Unknown includes beneficiaries from territories and beneficiaries whose address information is being updated.

Medicare beneficiaries with income below 150% of poverty ($16,245/individual; $21,855/couple in 2009) and limited resources ($12,510/individual; $25,010/couple in 2009) are eligible for additional premium and cost-sharing assistance for prescriptions drugs under Part D of the Medicare program. For more information on the low-income subsidy, see Kaiser's Fact Sheet on Low-Income Assistance Under the Medicare Drug Benefit.

Centers for Medicare and Medicaid Services (CMS), released February 2009, available at http://www.cms.hhs.gov/prescriptiondrugcovgenIn/.

MSP: Medicare Savings Program: Assist low-income beneficiaries by helping to pay Medicare premiums and, in some instances, cost-sharing for other Medicare services.
SSI: Supplemental Security Income