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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 | 1 |
| 1970 | 3 |
| 1971 | 2 |
| 1972 | 3 |
| 1973 | 3 |
| 1976 | 8 |
| 1977 | 5 |
| 1978 | 6 |
| 1979 | 5 |
| 1980 | 1 |
| 1983 | 1 |
| 1985 | 2 |
| 1991 | 1 |
| 1993 | 1 |
| 1994 | 1 |
| 1996 | 3 |
| 2001 | 1 |
| 2002 | 1 |
| 2005 | 2 |
| 2007 | 1 |
| 2008 | 1 |
| 2009 | 2 |
| 2010 | 1 |
| 2012 | 2 |
| 2013 | 2 |
| 2014 | 1 |
| 2015 | 2 |
| 2016 | 3 |
| 2017 | 4 |
| 2018 | 8 |
| 2019 | 7 |
| 2020 | 11 |
| 2021 | 15 |
| 2022 | 17 |
| 2023 | 23 |
| 2024 | 30 |
| 2025 | 22 |