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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 1 |
| 1958 | 4 |
| 1959 | 2 |
| 1960 | 2 |
| 1961 | 2 |
| 1962 | 1 |
| 1964 | 3 |
| 1965 | 2 |
| 1966 | 1 |
| 1968 | 2 |
| 1969 | 2 |
| 1971 | 8 |
| 1972 | 1 |
| 1973 | 1 |
| 1975 | 1 |
| 1977 | 1 |
| 1981 | 1 |
| 1985 | 1 |
| 1987 | 1 |
| 1988 | 2 |
| 1991 | 2 |
| 1992 | 1 |
| 1993 | 2 |
| 1994 | 1 |
| 1997 | 1 |
| 2009 | 1 |
| 2010 | 1 |
| 2013 | 1 |
| 2014 | 3 |
| 2016 | 1 |
| 2017 | 1 |
| 2019 | 1 |
| 2020 | 1 |
| 2022 | 1 |
| 2023 | 3 |
| 2024 | 2 |
| 2025 | 2 |