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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 |
| 1954 | 1 |
| 1955 | 2 |
| 1956 | 3 |
| 1957 | 4 |
| 1958 | 4 |
| 1959 | 8 |
| 1960 | 10 |
| 1961 | 4 |
| 1962 | 8 |
| 1963 | 6 |
| 1964 | 8 |
| 1965 | 8 |
| 1966 | 15 |
| 1967 | 11 |
| 1968 | 18 |
| 1969 | 8 |
| 1970 | 15 |
| 1971 | 9 |
| 1972 | 3 |
| 1974 | 1 |
| 1977 | 2 |
| 2023 | 0 |