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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 |
|---|---|
| 1957 | 2 |
| 1960 | 1 |
| 1961 | 1 |
| 1962 | 1 |
| 1964 | 2 |
| 1966 | 1 |
| 1968 | 1 |
| 1970 | 1 |
| 1971 | 1 |
| 1972 | 1 |
| 1981 | 2 |
| 1982 | 1 |
| 1983 | 2 |
| 1984 | 1 |
| 1985 | 2 |
| 1986 | 2 |
| 1987 | 1 |
| 1988 | 1 |
| 1989 | 2 |
| 1991 | 1 |
| 1995 | 2 |
| 1997 | 3 |
| 2002 | 1 |
| 2004 | 2 |
| 2011 | 1 |
| 2013 | 2 |
| 2015 | 1 |
| 2021 | 1 |
| 2023 | 1 |
| 2024 | 1 |