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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 1 |
| 1965 | 1 |
| 1966 | 6 |
| 1967 | 11 |
| 1968 | 5 |
| 1969 | 11 |
| 1970 | 16 |
| 1971 | 29 |
| 1972 | 43 |
| 1973 | 58 |
| 1974 | 70 |
| 1975 | 79 |
| 1976 | 53 |
| 1977 | 89 |
| 1978 | 134 |
| 1979 | 157 |
| 1980 | 134 |
| 1981 | 178 |
| 1982 | 213 |
| 1983 | 181 |
| 1984 | 205 |
| 1985 | 164 |
| 1986 | 200 |
| 1987 | 208 |
| 1988 | 255 |
| 1989 | 289 |
| 1990 | 292 |
| 1991 | 306 |
| 1992 | 271 |
| 1993 | 298 |
| 1994 | 276 |
| 1995 | 296 |
| 1996 | 252 |
| 1997 | 269 |
| 1998 | 256 |
| 1999 | 236 |
| 2000 | 240 |
| 2001 | 331 |
| 2002 | 243 |
| 2003 | 260 |
| 2004 | 219 |
| 2005 | 216 |
| 2006 | 218 |
| 2007 | 180 |
| 2008 | 200 |
| 2009 | 172 |
| 2010 | 202 |
| 2011 | 173 |
| 2012 | 174 |
| 2013 | 155 |
| 2014 | 154 |
| 2015 | 136 |
| 2016 | 144 |
| 2017 | 111 |
| 2018 | 109 |
| 2019 | 101 |
| 2020 | 81 |
| 2021 | 72 |
| 2022 | 38 |
| 2023 | 24 |
| 2024 | 9 |