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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 |
|---|---|
| 1988 | 1 |
| 1989 | 8 |
| 1990 | 17 |
| 1991 | 20 |
| 1992 | 15 |
| 1993 | 24 |
| 1994 | 16 |
| 1995 | 18 |
| 1996 | 15 |
| 1997 | 19 |
| 1998 | 11 |
| 1999 | 16 |
| 2000 | 4 |
| 2001 | 2 |
| 2002 | 2 |
| 2003 | 2 |
| 2009 | 1 |
| 2010 | 2 |
| 2011 | 2 |
| 2012 | 1 |
| 2013 | 1 |
| 2014 | 2 |
| 2015 | 1 |
| 2016 | 2 |
| 2019 | 2 |
| 2020 | 2 |
| 2021 | 6 |
| 2022 | 2 |
| 2023 | 1 |
| 2025 | 0 |