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Federal government websites often end in .gov or .mil. Before
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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 |
|---|---|
| 1965 | 1 |
| 1966 | 15 |
| 1967 | 26 |
| 1968 | 37 |
| 1969 | 33 |
| 1970 | 44 |
| 1971 | 70 |
| 1972 | 51 |
| 1973 | 49 |
| 1974 | 37 |
| 1975 | 48 |
| 1976 | 31 |
| 1977 | 38 |
| 1978 | 49 |
| 1979 | 32 |
| 1980 | 53 |
| 1981 | 47 |
| 1982 | 47 |
| 1983 | 40 |
| 1984 | 47 |
| 1985 | 43 |
| 1986 | 62 |
| 1987 | 61 |
| 1988 | 68 |
| 1989 | 39 |
| 1990 | 16 |
| 2024 | 0 |