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The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
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The https:// ensures that you are connecting to the
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and transmitted securely.
Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1961 | 1 |
| 1963 | 2 |
| 1964 | 2 |
| 1965 | 1 |
| 1966 | 4 |
| 1967 | 2 |
| 1969 | 1 |
| 1970 | 2 |
| 1971 | 3 |
| 1974 | 1 |
| 1977 | 4 |
| 1978 | 1 |
| 1979 | 4 |
| 1980 | 4 |
| 1981 | 2 |
| 1982 | 1 |
| 1983 | 3 |
| 1984 | 2 |
| 1986 | 2 |
| 1987 | 2 |
| 1988 | 3 |
| 1989 | 4 |
| 1990 | 5 |
| 1992 | 3 |
| 1993 | 1 |
| 1994 | 2 |
| 1995 | 1 |
| 1997 | 1 |
| 1998 | 1 |
| 1999 | 1 |
| 2001 | 1 |
| 2023 | 0 |