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Federal government websites often end in .gov or .mil. Before
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and transmitted securely.
Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1971 | 2 |
| 1972 | 3 |
| 1973 | 2 |
| 1974 | 3 |
| 1975 | 2 |
| 1976 | 13 |
| 1977 | 4 |
| 1978 | 4 |
| 1979 | 2 |
| 1980 | 2 |
| 1981 | 5 |
| 1982 | 2 |
| 1983 | 1 |
| 1987 | 1 |
| 1999 | 1 |
| 2000 | 1 |
| 2003 | 1 |
| 2006 | 1 |
| 2017 | 2 |
| 2018 | 1 |
| 2019 | 1 |
| 2024 | 0 |