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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 4 |
| 1965 | 5 |
| 1966 | 4 |
| 1967 | 21 |
| 1968 | 14 |
| 1969 | 15 |
| 1970 | 19 |
| 1971 | 25 |
| 1972 | 23 |
| 1973 | 21 |
| 1974 | 25 |
| 1975 | 15 |
| 1976 | 10 |
| 1977 | 20 |
| 1978 | 24 |
| 1979 | 28 |
| 1980 | 33 |
| 1981 | 46 |
| 1982 | 37 |
| 1983 | 38 |
| 1984 | 75 |
| 1985 | 59 |
| 1986 | 86 |
| 1987 | 121 |
| 1988 | 117 |
| 1989 | 126 |
| 1990 | 141 |
| 1991 | 135 |
| 1992 | 160 |
| 1993 | 165 |
| 1994 | 168 |
| 1995 | 197 |
| 1996 | 236 |
| 1997 | 263 |
| 1998 | 274 |
| 1999 | 272 |
| 2000 | 203 |
| 2001 | 207 |
| 2002 | 183 |
| 2003 | 202 |
| 2004 | 216 |
| 2005 | 219 |
| 2006 | 250 |
| 2007 | 264 |
| 2008 | 286 |
| 2009 | 300 |
| 2010 | 347 |
| 2011 | 416 |
| 2012 | 465 |
| 2013 | 487 |
| 2014 | 495 |
| 2015 | 508 |
| 2016 | 463 |
| 2017 | 523 |
| 2018 | 539 |
| 2019 | 502 |
| 2020 | 507 |
| 2021 | 409 |
| 2022 | 341 |
| 2023 | 128 |