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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 |
|---|---|
| 1968 | 4 |
| 1971 | 1 |
| 1972 | 1 |
| 1975 | 1 |
| 1976 | 1 |
| 1977 | 2 |
| 1980 | 1 |
| 1986 | 1 |
| 1989 | 2 |
| 1990 | 1 |
| 1991 | 1 |
| 1992 | 1 |
| 1993 | 1 |
| 1995 | 4 |
| 1998 | 5 |
| 1999 | 3 |
| 2001 | 2 |
| 2002 | 2 |
| 2003 | 2 |
| 2004 | 2 |
| 2005 | 3 |
| 2006 | 1 |
| 2007 | 3 |
| 2008 | 1 |
| 2012 | 3 |
| 2013 | 2 |
| 2015 | 2 |
| 2016 | 3 |
| 2017 | 2 |
| 2018 | 2 |
| 2019 | 4 |
| 2020 | 3 |
| 2021 | 5 |
| 2022 | 12 |
| 2023 | 1 |