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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 |
|---|---|
| 1988 | 2 |
| 1989 | 2 |
| 1990 | 2 |
| 1991 | 1 |
| 1992 | 1 |
| 1995 | 2 |
| 1996 | 3 |
| 1997 | 3 |
| 1999 | 3 |
| 2000 | 5 |
| 2001 | 13 |
| 2002 | 7 |
| 2003 | 37 |
| 2004 | 50 |
| 2005 | 55 |
| 2006 | 68 |
| 2007 | 54 |
| 2008 | 75 |
| 2009 | 97 |
| 2010 | 115 |
| 2011 | 145 |
| 2012 | 171 |
| 2013 | 226 |
| 2014 | 369 |
| 2015 | 534 |
| 2016 | 597 |
| 2017 | 760 |
| 2018 | 1004 |
| 2019 | 1148 |
| 2020 | 1595 |
| 2021 | 1826 |
| 2022 | 2246 |
| 2023 | 2356 |
| 2024 | 1101 |