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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 |
|---|---|
| 1960 | 2 |
| 1968 | 3 |
| 1969 | 1 |
| 1970 | 2 |
| 1972 | 2 |
| 1973 | 3 |
| 1974 | 4 |
| 1975 | 1 |
| 1976 | 5 |
| 1977 | 1 |
| 1978 | 3 |
| 1979 | 3 |
| 1980 | 6 |
| 1981 | 6 |
| 1982 | 6 |
| 1983 | 3 |
| 1984 | 1 |
| 1987 | 6 |
| 1988 | 4 |
| 1989 | 2 |
| 1990 | 1 |
| 1992 | 2 |
| 1994 | 2 |
| 1999 | 1 |
| 2000 | 1 |
| 2002 | 1 |
| 2005 | 1 |
| 2010 | 1 |
| 2011 | 1 |
| 2013 | 4 |
| 2014 | 2 |
| 2015 | 2 |
| 2016 | 3 |
| 2017 | 1 |
| 2018 | 3 |
| 2021 | 1 |
| 2022 | 1 |
| 2023 | 0 |