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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
government site.
The site is secure.
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 |
|---|---|
| 1955 | 1 |
| 1956 | 2 |
| 1957 | 1 |
| 1958 | 2 |
| 1961 | 2 |
| 1963 | 2 |
| 1964 | 1 |
| 1965 | 2 |
| 1966 | 2 |
| 1967 | 2 |
| 1968 | 7 |
| 1969 | 1 |
| 1970 | 1 |
| 1972 | 2 |
| 2005 | 1 |
| 2009 | 1 |
| 2011 | 1 |
| 2014 | 2 |
| 2015 | 1 |
| 2016 | 1 |
| 2017 | 2 |
| 2018 | 3 |
| 2019 | 2 |
| 2020 | 1 |
| 2021 | 5 |
| 2022 | 2 |
| 2023 | 4 |
| 2024 | 1 |