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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 |
|---|---|
| 1957 | 1 |
| 1958 | 1 |
| 1959 | 2 |
| 1961 | 1 |
| 1962 | 2 |
| 1963 | 3 |
| 1965 | 3 |
| 1966 | 2 |
| 1967 | 4 |
| 1968 | 1 |
| 1969 | 1 |
| 1971 | 4 |
| 1972 | 4 |
| 1973 | 4 |
| 1974 | 8 |
| 1975 | 6 |
| 1976 | 1 |
| 1978 | 3 |
| 1979 | 2 |
| 1980 | 3 |
| 1982 | 1 |
| 1983 | 2 |
| 1984 | 3 |
| 1985 | 4 |
| 1986 | 4 |
| 1987 | 1 |
| 2025 | 0 |