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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 |
|---|---|
| 1969 | 1 |
| 1970 | 1 |
| 1971 | 2 |
| 1972 | 1 |
| 1973 | 2 |
| 1974 | 1 |
| 1975 | 2 |
| 1976 | 2 |
| 1978 | 1 |
| 1981 | 1 |
| 1983 | 1 |
| 1985 | 1 |
| 1986 | 1 |
| 2007 | 1 |
| 2008 | 1 |
| 2012 | 1 |
| 2013 | 1 |
| 2015 | 1 |
| 2016 | 2 |
| 2017 | 1 |
| 2018 | 1 |
| 2024 | 1 |