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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1967 | 2 |
| 1968 | 5 |
| 1969 | 8 |
| 1970 | 7 |
| 1971 | 10 |
| 1972 | 3 |
| 1973 | 11 |
| 1974 | 21 |
| 1975 | 34 |
| 1976 | 17 |
| 1977 | 51 |
| 1978 | 135 |
| 1979 | 91 |
| 1980 | 82 |
| 1981 | 86 |
| 1982 | 101 |
| 1983 | 116 |
| 1984 | 130 |
| 1985 | 109 |
| 1986 | 92 |
| 1987 | 110 |
| 1988 | 111 |
| 1989 | 175 |
| 1990 | 180 |
| 1991 | 154 |
| 1992 | 151 |
| 1993 | 146 |
| 1994 | 138 |
| 1995 | 144 |
| 1996 | 117 |
| 1997 | 163 |
| 1998 | 166 |
| 1999 | 150 |
| 2000 | 181 |
| 2001 | 152 |
| 2002 | 175 |
| 2003 | 177 |
| 2004 | 220 |
| 2005 | 185 |
| 2006 | 202 |
| 2007 | 201 |
| 2008 | 179 |
| 2009 | 182 |
| 2010 | 181 |
| 2011 | 155 |
| 2012 | 151 |
| 2013 | 158 |
| 2014 | 141 |
| 2015 | 150 |
| 2016 | 136 |
| 2017 | 120 |
| 2018 | 117 |
| 2019 | 106 |
| 2020 | 85 |
| 2021 | 17 |
| 2022 | 1 |
| 2023 | 1 |
| 2024 | 1 |