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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 |
|---|---|
| 1972 | 1 |
| 1976 | 2 |
| 1981 | 1 |
| 1987 | 1 |
| 1991 | 2 |
| 1992 | 3 |
| 1993 | 1 |
| 1995 | 3 |
| 1996 | 4 |
| 1997 | 2 |
| 1998 | 3 |
| 1999 | 3 |
| 2001 | 4 |
| 2002 | 1 |
| 2005 | 1 |
| 2006 | 2 |
| 2007 | 3 |
| 2008 | 2 |
| 2009 | 1 |
| 2010 | 5 |
| 2011 | 5 |
| 2012 | 2 |
| 2013 | 1 |
| 2015 | 1 |
| 2020 | 1 |
| 2021 | 3 |
| 2024 | 1 |
| 2025 | 1 |