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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1951 | 3 |
| 1952 | 1 |
| 1954 | 3 |
| 1957 | 2 |
| 1958 | 1 |
| 1959 | 1 |
| 1960 | 3 |
| 1961 | 4 |
| 1963 | 2 |
| 1964 | 1 |
| 1966 | 2 |
| 1967 | 2 |
| 1968 | 2 |
| 1970 | 1 |
| 1971 | 1 |
| 1972 | 1 |
| 1973 | 2 |
| 1980 | 1 |
| 1981 | 2 |
| 1985 | 1 |
| 1987 | 1 |
| 1988 | 1 |
| 2008 | 1 |
| 2010 | 1 |
| 2012 | 3 |
| 2013 | 1 |
| 2014 | 4 |
| 2015 | 2 |
| 2016 | 2 |
| 2017 | 3 |
| 2018 | 3 |
| 2019 | 2 |
| 2020 | 1 |
| 2022 | 1 |
| 2023 | 3 |
| 2024 | 1 |
| 2025 | 2 |