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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 4 |
| 1959 | 3 |
| 1960 | 2 |
| 1961 | 2 |
| 1963 | 1 |
| 1964 | 2 |
| 1966 | 2 |
| 1967 | 3 |
| 1968 | 4 |
| 1969 | 1 |
| 1970 | 2 |
| 1971 | 3 |
| 1972 | 1 |
| 1973 | 2 |
| 1974 | 1 |
| 1975 | 1 |
| 1982 | 1 |
| 1985 | 1 |
| 1986 | 1 |
| 1987 | 3 |
| 1988 | 2 |
| 1990 | 1 |
| 1991 | 1 |
| 1992 | 1 |
| 1993 | 2 |
| 1995 | 1 |
| 1996 | 2 |
| 1998 | 2 |
| 2001 | 1 |
| 2002 | 1 |
| 2003 | 2 |
| 2006 | 2 |
| 2007 | 1 |
| 2012 | 1 |
| 2020 | 1 |
| 2021 | 2 |
| 2022 | 1 |
| 2023 | 1 |
| 2024 | 2 |