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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 |
|---|---|
| 1955 | 1 |
| 1967 | 1 |
| 1973 | 1 |
| 1975 | 2 |
| 1976 | 3 |
| 1979 | 2 |
| 1980 | 1 |
| 1981 | 3 |
| 1983 | 2 |
| 1987 | 2 |
| 1989 | 1 |
| 1990 | 1 |
| 1991 | 1 |
| 1998 | 1 |
| 1999 | 1 |
| 2010 | 1 |
| 2011 | 1 |
| 2012 | 2 |
| 2013 | 3 |
| 2014 | 3 |
| 2015 | 3 |
| 2016 | 4 |
| 2017 | 5 |
| 2018 | 3 |
| 2019 | 5 |
| 2020 | 3 |
| 2021 | 4 |
| 2022 | 3 |
| 2023 | 1 |