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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1972 | 1 |
| 1973 | 1 |
| 1974 | 2 |
| 1975 | 1 |
| 1976 | 1 |
| 1977 | 1 |
| 1978 | 2 |
| 1981 | 2 |
| 1982 | 2 |
| 1983 | 1 |
| 1985 | 1 |
| 1986 | 2 |
| 1987 | 2 |
| 1988 | 1 |
| 1989 | 2 |
| 1991 | 4 |
| 1992 | 1 |
| 1994 | 1 |
| 1996 | 1 |
| 1997 | 2 |
| 2005 | 1 |
| 2006 | 1 |
| 2011 | 1 |
| 2012 | 3 |
| 2013 | 5 |
| 2014 | 5 |
| 2015 | 3 |
| 2016 | 5 |
| 2018 | 3 |
| 2019 | 2 |
| 2020 | 3 |
| 2021 | 5 |
| 2022 | 3 |
| 2023 | 5 |
| 2024 | 4 |
| 2025 | 3 |
| 2026 | 3 |