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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1959 | 2 |
| 1960 | 2 |
| 1961 | 1 |
| 1962 | 2 |
| 1963 | 2 |
| 1964 | 5 |
| 1966 | 2 |
| 1968 | 1 |
| 1970 | 1 |
| 1974 | 2 |
| 1976 | 3 |
| 1977 | 1 |
| 1978 | 2 |
| 1979 | 1 |
| 1986 | 1 |
| 1988 | 1 |
| 1989 | 1 |
| 1990 | 2 |
| 1991 | 3 |
| 1992 | 2 |
| 1994 | 2 |
| 1997 | 7 |
| 1999 | 1 |
| 2000 | 1 |
| 2009 | 1 |
| 2010 | 2 |
| 2011 | 1 |
| 2012 | 3 |
| 2013 | 1 |
| 2014 | 2 |
| 2015 | 1 |
| 2016 | 2 |
| 2017 | 2 |
| 2018 | 1 |
| 2020 | 1 |
| 2021 | 4 |
| 2022 | 1 |
| 2024 | 3 |
| 2025 | 4 |