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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 1 |
| 1965 | 9 |
| 1966 | 23 |
| 1967 | 19 |
| 1968 | 40 |
| 1969 | 34 |
| 1970 | 42 |
| 1971 | 48 |
| 1972 | 69 |
| 1973 | 99 |
| 1974 | 101 |
| 1975 | 103 |
| 1976 | 108 |
| 1977 | 145 |
| 1978 | 145 |
| 1979 | 129 |
| 1980 | 179 |
| 1981 | 145 |
| 1982 | 139 |
| 1983 | 133 |
| 1984 | 107 |
| 1985 | 159 |
| 1986 | 147 |
| 1987 | 144 |
| 1988 | 178 |
| 1989 | 201 |
| 1990 | 216 |
| 1991 | 225 |
| 1992 | 242 |
| 1993 | 346 |
| 1994 | 351 |
| 1995 | 360 |
| 1996 | 324 |
| 1997 | 337 |
| 1998 | 327 |
| 1999 | 237 |
| 2000 | 234 |
| 2001 | 231 |
| 2002 | 254 |
| 2003 | 267 |
| 2004 | 273 |
| 2005 | 255 |
| 2006 | 203 |
| 2007 | 174 |
| 2008 | 167 |
| 2009 | 149 |
| 2010 | 152 |
| 2011 | 177 |
| 2012 | 157 |
| 2013 | 139 |
| 2014 | 106 |
| 2015 | 88 |
| 2016 | 71 |
| 2017 | 73 |
| 2018 | 55 |
| 2019 | 51 |
| 2020 | 47 |
| 2021 | 32 |
| 2022 | 6 |
| 2023 | 5 |
| 2024 | 2 |