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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1952 | 1 |
| 1954 | 3 |
| 1956 | 1 |
| 1958 | 1 |
| 1960 | 2 |
| 1963 | 1 |
| 1965 | 1 |
| 1967 | 1 |
| 1969 | 2 |
| 1972 | 1 |
| 1973 | 2 |
| 1978 | 1 |
| 1979 | 2 |
| 1980 | 1 |
| 1981 | 1 |
| 1983 | 2 |
| 1986 | 1 |
| 1987 | 1 |
| 1997 | 2 |
| 2006 | 1 |
| 2012 | 1 |
| 2013 | 1 |
| 2015 | 1 |
| 2016 | 2 |
| 2017 | 2 |
| 2018 | 3 |
| 2019 | 1 |
| 2020 | 2 |
| 2021 | 4 |
| 2024 | 2 |
| 2025 | 3 |