The data include:
The Death Master File is a subset of the Social Security Administration's Numident database file, computerized in 1962, which contains information about all Social Security numbers issued since 1936. The Death Master File is considered a public document under the Freedom of Information Act, and monthly and weekly updates of the file are sold by the National Technical Information Service of the U.S. Department of Commerce. It is used by financial and credit firms and government agencies to match records and prevent identity fraud.
The Death Master File, in its SSDI form, is also used extensively by genealogists. Lorretto Dennis Szucs and Sandra Hargraves Luebking report in The Source: A Guidebook of American Genealogy (1997) that the total number of deaths in the United States from 1962 to September 1991 is estimated at 58.2 million. Of that number, 42.5 million (73 percent) are found in the Death Master File. Other research published by the Social Security Administration in 2002 suggests that for most years since 1973, 93 percent to 96 percent of deaths of individuals aged 65 or older were included in the DMF. Today the number of deaths, at any age, reported to the Death Master File is around 95 percent.