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Federal government websites often end in .gov or .mil. Before
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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 |
| 1973 | 2 |
| 1988 | 1 |
| 1989 | 1 |
| 1990 | 2 |
| 1991 | 1 |
| 1992 | 1 |
| 1993 | 2 |
| 1994 | 2 |
| 1999 | 1 |
| 2002 | 1 |
| 2003 | 1 |
| 2004 | 3 |
| 2005 | 1 |
| 2006 | 3 |
| 2007 | 3 |
| 2008 | 2 |
| 2009 | 11 |
| 2010 | 9 |
| 2011 | 10 |
| 2012 | 7 |
| 2013 | 10 |
| 2014 | 9 |
| 2015 | 9 |
| 2016 | 9 |
| 2017 | 16 |
| 2018 | 20 |
| 2019 | 21 |
| 2020 | 25 |
| 2021 | 27 |
| 2022 | 22 |
| 2023 | 21 |
| 2024 | 2 |