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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1967 | 1 |
| 1970 | 1 |
| 1971 | 1 |
| 1972 | 3 |
| 1979 | 1 |
| 1984 | 1 |
| 1985 | 1 |
| 1986 | 2 |
| 1987 | 1 |
| 1988 | 4 |
| 1989 | 1 |
| 1990 | 1 |
| 1992 | 3 |
| 1994 | 1 |
| 1995 | 2 |
| 1996 | 3 |
| 1998 | 1 |
| 2000 | 1 |
| 2005 | 1 |
| 2006 | 1 |
| 2007 | 3 |
| 2008 | 3 |
| 2010 | 2 |
| 2015 | 3 |
| 2016 | 7 |
| 2017 | 3 |
| 2018 | 4 |
| 2019 | 2 |
| 2025 | 0 |