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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1956 | 2 |
| 1958 | 2 |
| 1959 | 2 |
| 1963 | 1 |
| 1964 | 1 |
| 1965 | 1 |
| 1966 | 2 |
| 1968 | 1 |
| 1969 | 1 |
| 1970 | 1 |
| 1971 | 1 |
| 1973 | 1 |
| 1974 | 1 |
| 1975 | 3 |
| 1976 | 3 |
| 1977 | 1 |
| 1978 | 4 |
| 1979 | 3 |
| 1980 | 1 |
| 1981 | 1 |
| 1988 | 1 |
| 1993 | 2 |
| 1996 | 1 |
| 1997 | 3 |
| 1998 | 1 |
| 1999 | 2 |
| 2003 | 1 |
| 2017 | 1 |
| 2021 | 3 |
| 2022 | 1 |
| 2023 | 4 |