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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1954 | 1 |
| 1955 | 1 |
| 1959 | 1 |
| 1961 | 1 |
| 1963 | 2 |
| 1966 | 1 |
| 1967 | 1 |
| 1968 | 1 |
| 1969 | 2 |
| 1970 | 2 |
| 1971 | 1 |
| 1972 | 1 |
| 1974 | 2 |
| 1975 | 1 |
| 1976 | 2 |
| 1978 | 1 |
| 1980 | 1 |
| 1981 | 1 |
| 1982 | 3 |
| 1984 | 1 |
| 1999 | 1 |
| 2004 | 2 |
| 2008 | 1 |
| 2010 | 1 |
| 2011 | 3 |
| 2013 | 1 |
| 2014 | 2 |
| 2015 | 5 |
| 2016 | 2 |
| 2017 | 2 |
| 2018 | 3 |
| 2019 | 2 |
| 2020 | 2 |
| 2021 | 3 |
| 2022 | 3 |
| 2023 | 1 |