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The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
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 |
|---|---|
| 1973 | 1 |
| 1978 | 1 |
| 1982 | 1 |
| 1984 | 2 |
| 1985 | 2 |
| 1986 | 2 |
| 1988 | 1 |
| 1990 | 1 |
| 1991 | 1 |
| 1993 | 2 |
| 1996 | 1 |
| 1998 | 1 |
| 2002 | 1 |
| 2007 | 1 |
| 2011 | 2 |
| 2012 | 2 |
| 2013 | 3 |
| 2014 | 2 |
| 2016 | 1 |
| 2018 | 2 |
| 2019 | 2 |
| 2020 | 1 |
| 2021 | 1 |
| 2023 | 2 |
| 2024 | 1 |