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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 1 |
| 1958 | 1 |
| 1959 | 6 |
| 1960 | 4 |
| 1961 | 1 |
| 1962 | 1 |
| 1966 | 1 |
| 1969 | 1 |
| 1970 | 1 |
| 1972 | 2 |
| 1975 | 2 |
| 1979 | 1 |
| 1981 | 2 |
| 1983 | 1 |
| 1984 | 1 |
| 1985 | 3 |
| 1986 | 4 |
| 1987 | 4 |
| 1988 | 2 |
| 1989 | 5 |
| 1990 | 4 |
| 1991 | 7 |
| 1992 | 4 |
| 1994 | 2 |
| 1995 | 2 |
| 1998 | 1 |
| 1999 | 4 |
| 2000 | 2 |
| 2001 | 1 |
| 2003 | 2 |
| 2004 | 2 |
| 2012 | 2 |
| 2013 | 3 |
| 2014 | 2 |
| 2017 | 1 |
| 2018 | 2 |
| 2019 | 1 |
| 2022 | 1 |
| 2023 | 1 |
| 2024 | 0 |