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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 |
|---|---|
| 1964 | 19 |
| 1965 | 39 |
| 1966 | 37 |
| 1967 | 27 |
| 1968 | 49 |
| 1969 | 56 |
| 1970 | 61 |
| 1971 | 64 |
| 1972 | 64 |
| 1973 | 58 |
| 1974 | 103 |
| 1975 | 62 |
| 1976 | 50 |
| 1977 | 53 |
| 1978 | 51 |
| 1979 | 44 |
| 1980 | 25 |
| 1981 | 18 |
| 1982 | 27 |
| 1983 | 29 |
| 1984 | 24 |
| 1985 | 28 |
| 1986 | 26 |
| 1987 | 26 |
| 1988 | 18 |
| 2026 | 0 |