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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1967 | 3 |
| 1968 | 8 |
| 1969 | 21 |
| 1970 | 10 |
| 1971 | 18 |
| 1972 | 25 |
| 1973 | 34 |
| 1974 | 40 |
| 1975 | 67 |
| 1976 | 41 |
| 1977 | 49 |
| 1978 | 47 |
| 1979 | 59 |
| 1980 | 54 |
| 1981 | 60 |
| 1982 | 65 |
| 1983 | 106 |
| 1984 | 117 |
| 1985 | 122 |
| 1986 | 127 |
| 1987 | 138 |
| 1988 | 161 |
| 1989 | 157 |
| 1990 | 159 |
| 1991 | 182 |
| 1992 | 200 |
| 1993 | 169 |
| 1994 | 171 |
| 1995 | 166 |
| 1996 | 153 |
| 1997 | 147 |
| 1998 | 165 |
| 1999 | 153 |
| 2000 | 163 |
| 2001 | 157 |
| 2002 | 171 |
| 2003 | 145 |
| 2004 | 157 |
| 2005 | 175 |
| 2006 | 224 |
| 2007 | 225 |
| 2008 | 182 |
| 2009 | 175 |
| 2010 | 193 |
| 2011 | 189 |
| 2012 | 189 |
| 2013 | 192 |
| 2014 | 191 |
| 2015 | 182 |
| 2016 | 172 |
| 2017 | 163 |
| 2018 | 178 |
| 2019 | 156 |
| 2020 | 132 |
| 2021 | 116 |
| 2022 | 89 |
| 2023 | 24 |