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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1961 | 1 |
| 1964 | 1 |
| 1965 | 4 |
| 1966 | 3 |
| 1967 | 1 |
| 1968 | 2 |
| 1969 | 4 |
| 1970 | 6 |
| 1971 | 2 |
| 1972 | 2 |
| 1974 | 2 |
| 1976 | 2 |
| 1977 | 7 |
| 1978 | 7 |
| 1979 | 8 |
| 1980 | 5 |
| 1981 | 1 |
| 1983 | 5 |
| 1984 | 5 |
| 1985 | 12 |
| 1986 | 10 |
| 1987 | 5 |
| 1988 | 11 |
| 1989 | 13 |
| 1990 | 12 |
| 1991 | 12 |
| 1992 | 16 |
| 1993 | 33 |
| 1994 | 31 |
| 1995 | 53 |
| 1996 | 37 |
| 1997 | 53 |
| 1998 | 48 |
| 1999 | 70 |
| 2000 | 75 |
| 2001 | 84 |
| 2002 | 64 |
| 2003 | 53 |
| 2004 | 75 |
| 2005 | 90 |
| 2006 | 107 |
| 2007 | 135 |
| 2008 | 120 |
| 2009 | 134 |
| 2010 | 183 |
| 2011 | 162 |
| 2012 | 127 |
| 2013 | 125 |
| 2014 | 135 |
| 2015 | 148 |
| 2016 | 112 |
| 2017 | 82 |
| 2018 | 77 |
| 2019 | 77 |
| 2020 | 74 |
| 2021 | 54 |
| 2022 | 3 |
| 2023 | 5 |
| 2024 | 2 |