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Federal government websites often end in .gov or .mil. Before
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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1956 | 2 |
| 1957 | 1 |
| 1960 | 1 |
| 1961 | 2 |
| 1962 | 1 |
| 1963 | 1 |
| 1964 | 1 |
| 1965 | 1 |
| 1966 | 2 |
| 1970 | 1 |
| 1972 | 1 |
| 1973 | 2 |
| 1974 | 2 |
| 1976 | 2 |
| 1981 | 1 |
| 1997 | 1 |
| 2007 | 1 |
| 2008 | 1 |
| 2009 | 1 |
| 2011 | 1 |
| 2012 | 3 |
| 2013 | 4 |
| 2014 | 3 |
| 2015 | 2 |
| 2016 | 1 |
| 2017 | 3 |
| 2018 | 1 |
| 2019 | 2 |
| 2020 | 2 |
| 2021 | 1 |
| 2022 | 6 |
| 2023 | 2 |
| 2024 | 1 |