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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 1 |
| 1959 | 3 |
| 1960 | 2 |
| 1961 | 2 |
| 1962 | 2 |
| 1963 | 2 |
| 1964 | 1 |
| 1966 | 2 |
| 1967 | 1 |
| 1970 | 2 |
| 1971 | 3 |
| 1974 | 1 |
| 1975 | 1 |
| 1976 | 1 |
| 1977 | 2 |
| 1979 | 1 |
| 1987 | 1 |
| 1997 | 1 |
| 1999 | 1 |
| 2002 | 1 |
| 2003 | 1 |
| 2007 | 1 |
| 2009 | 3 |
| 2011 | 2 |
| 2013 | 5 |
| 2014 | 2 |
| 2015 | 2 |
| 2016 | 1 |
| 2017 | 7 |
| 2018 | 2 |
| 2019 | 2 |
| 2020 | 7 |
| 2021 | 9 |
| 2022 | 3 |
| 2023 | 1 |
| 2024 | 2 |