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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 |
|---|---|
| 1957 | 1 |
| 1959 | 1 |
| 1960 | 1 |
| 1962 | 1 |
| 1966 | 1 |
| 1968 | 1 |
| 1970 | 2 |
| 1971 | 1 |
| 1972 | 2 |
| 1974 | 1 |
| 1977 | 2 |
| 1979 | 1 |
| 1980 | 1 |
| 1983 | 1 |
| 1991 | 1 |
| 1994 | 1 |
| 1998 | 1 |
| 1999 | 2 |
| 2003 | 1 |
| 2004 | 2 |
| 2005 | 3 |
| 2006 | 1 |
| 2007 | 1 |
| 2010 | 1 |
| 2013 | 1 |
| 2015 | 1 |
| 2017 | 1 |
| 2018 | 2 |
| 2019 | 2 |
| 2020 | 7 |
| 2021 | 11 |
| 2022 | 9 |
| 2023 | 1 |