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The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
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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 | 2 |
| 1967 | 1 |
| 1969 | 1 |
| 1971 | 1 |
| 1972 | 2 |
| 1973 | 2 |
| 1975 | 2 |
| 1976 | 3 |
| 1977 | 4 |
| 1978 | 2 |
| 1979 | 3 |
| 1980 | 2 |
| 1981 | 1 |
| 1982 | 2 |
| 2002 | 1 |
| 2003 | 1 |
| 2004 | 1 |
| 2007 | 1 |
| 2008 | 1 |
| 2010 | 4 |
| 2011 | 4 |
| 2012 | 2 |
| 2013 | 6 |
| 2014 | 10 |
| 2015 | 11 |
| 2016 | 9 |
| 2017 | 12 |
| 2018 | 12 |
| 2019 | 8 |
| 2020 | 9 |
| 2021 | 11 |
| 2022 | 14 |
| 2023 | 16 |
| 2024 | 12 |
| 2025 | 11 |