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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 1 |
| 1965 | 2 |
| 1966 | 14 |
| 1967 | 14 |
| 1968 | 34 |
| 1969 | 15 |
| 1970 | 19 |
| 1971 | 33 |
| 1972 | 25 |
| 1973 | 22 |
| 1974 | 18 |
| 1975 | 24 |
| 1976 | 23 |
| 1977 | 28 |
| 1978 | 37 |
| 1979 | 61 |
| 1980 | 54 |
| 1981 | 47 |
| 1982 | 56 |
| 1983 | 69 |
| 1984 | 59 |
| 1985 | 97 |
| 1986 | 58 |
| 1987 | 84 |
| 1988 | 82 |
| 1989 | 69 |
| 1990 | 120 |
| 1991 | 150 |
| 1992 | 119 |
| 1993 | 143 |
| 1994 | 135 |
| 1995 | 130 |
| 1996 | 126 |
| 1997 | 160 |
| 1998 | 126 |
| 1999 | 126 |
| 2000 | 120 |
| 2001 | 144 |
| 2002 | 118 |
| 2003 | 148 |
| 2004 | 143 |
| 2005 | 160 |
| 2006 | 176 |
| 2007 | 134 |
| 2008 | 185 |
| 2009 | 178 |
| 2010 | 201 |
| 2011 | 211 |
| 2012 | 231 |
| 2013 | 193 |
| 2014 | 179 |
| 2015 | 174 |
| 2016 | 159 |
| 2017 | 151 |
| 2018 | 128 |
| 2019 | 101 |
| 2020 | 116 |
| 2021 | 66 |
| 2022 | 60 |
| 2023 | 51 |
| 2024 | 26 |