The Social Security Administration administers a national program of contributory social insurance whereby employees, employers, and the self-employed pay contributions that are pooled in special trust funds. When earnings are reduced because of retirement, death, or disability, monthly benefits are paid to partially replace lost earnings. Part of the contributions go into a separate hospital insurance trust fund for workers when they become 65 to provide help with medical expenses. Other programs include the supplemental social security income program for the aged, blind, and disabled and the Old Age Survivors and Disability Insurance Program. SSA became an independent agency March 31, 1995. It had previously been part of the Department of Health, Education, and Welfare, later the Department of Health and Human Services. (From United States Government Manual, 1994-95).