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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 3 |
| 1965 | 23 |
| 1966 | 35 |
| 1967 | 51 |
| 1968 | 55 |
| 1969 | 84 |
| 1970 | 70 |
| 1971 | 100 |
| 1972 | 114 |
| 1973 | 116 |
| 1974 | 127 |
| 1975 | 133 |
| 1976 | 101 |
| 1977 | 153 |
| 1978 | 115 |
| 1979 | 143 |
| 1980 | 142 |
| 1981 | 142 |
| 1982 | 204 |
| 1983 | 215 |
| 1984 | 254 |
| 1985 | 287 |
| 1986 | 256 |
| 1987 | 302 |
| 1988 | 329 |
| 1989 | 317 |
| 1990 | 363 |
| 1991 | 384 |
| 1992 | 294 |
| 1993 | 350 |
| 1994 | 363 |
| 1995 | 329 |
| 1996 | 314 |
| 1997 | 346 |
| 1998 | 334 |
| 1999 | 338 |
| 2000 | 306 |
| 2001 | 313 |
| 2002 | 313 |
| 2003 | 270 |
| 2004 | 318 |
| 2005 | 300 |
| 2006 | 308 |
| 2007 | 314 |
| 2008 | 286 |
| 2009 | 253 |
| 2010 | 243 |
| 2011 | 248 |
| 2012 | 232 |
| 2013 | 206 |
| 2014 | 200 |
| 2015 | 204 |
| 2016 | 188 |
| 2017 | 172 |
| 2018 | 150 |
| 2019 | 134 |
| 2020 | 122 |
| 2021 | 83 |
| 2022 | 78 |
| 2023 | 58 |
| 2024 | 18 |