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Federal government websites often end in .gov or .mil. Before
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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1959 | 1 |
| 1972 | 2 |
| 1973 | 1 |
| 1975 | 2 |
| 1976 | 1 |
| 1977 | 1 |
| 1978 | 1 |
| 1979 | 5 |
| 1980 | 2 |
| 1981 | 2 |
| 1982 | 2 |
| 1983 | 1 |
| 1985 | 1 |
| 1986 | 3 |
| 1988 | 1 |
| 1990 | 2 |
| 1992 | 2 |
| 1993 | 1 |
| 1996 | 3 |
| 1998 | 2 |
| 1999 | 1 |
| 2000 | 2 |
| 2001 | 2 |
| 2002 | 2 |
| 2004 | 2 |
| 2006 | 1 |
| 2008 | 1 |
| 2015 | 1 |
| 2017 | 1 |
| 2019 | 1 |
| 2023 | 1 |
| 2024 | 1 |
| 2025 | 2 |