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The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
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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 |
|---|---|
| 1951 | 1 |
| 1965 | 1 |
| 1967 | 1 |
| 1968 | 1 |
| 1969 | 4 |
| 1971 | 1 |
| 1972 | 1 |
| 1973 | 2 |
| 1975 | 2 |
| 1979 | 2 |
| 1985 | 1 |
| 1987 | 1 |
| 1988 | 1 |
| 1989 | 1 |
| 1990 | 1 |
| 1991 | 2 |
| 1994 | 2 |
| 2012 | 2 |
| 2013 | 2 |
| 2014 | 1 |
| 2018 | 2 |
| 2020 | 3 |
| 2021 | 1 |
| 2022 | 2 |
| 2023 | 3 |
| 2025 | 2 |