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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1968 | 1 |
| 1971 | 1 |
| 1972 | 1 |
| 1973 | 1 |
| 1974 | 1 |
| 1978 | 1 |
| 1979 | 1 |
| 1981 | 1 |
| 1985 | 1 |
| 1986 | 1 |
| 1987 | 1 |
| 1988 | 2 |
| 1989 | 1 |
| 1990 | 2 |
| 1999 | 3 |
| 2000 | 2 |
| 2001 | 2 |
| 2003 | 1 |
| 2004 | 2 |
| 2007 | 1 |
| 2009 | 2 |
| 2010 | 1 |
| 2011 | 1 |
| 2012 | 1 |
| 2015 | 1 |
| 2017 | 1 |
| 2018 | 2 |
| 2019 | 2 |
| 2020 | 1 |
| 2021 | 1 |
| 2024 | 2 |