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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1962 | 4 |
| 1964 | 3 |
| 1965 | 1 |
| 1967 | 3 |
| 1969 | 1 |
| 1970 | 20 |
| 1971 | 49 |
| 1972 | 62 |
| 1973 | 39 |
| 1974 | 60 |
| 1975 | 73 |
| 1976 | 103 |
| 1977 | 116 |
| 1978 | 108 |
| 1979 | 88 |
| 1980 | 82 |
| 1981 | 138 |
| 1982 | 174 |
| 1983 | 156 |
| 1984 | 198 |
| 1985 | 255 |
| 1986 | 270 |
| 1987 | 332 |
| 1988 | 420 |
| 1989 | 468 |
| 1990 | 513 |
| 1991 | 545 |
| 1992 | 569 |
| 1993 | 575 |
| 1994 | 439 |
| 1995 | 502 |
| 1996 | 382 |
| 1997 | 398 |
| 1998 | 359 |
| 1999 | 258 |
| 2000 | 340 |
| 2001 | 317 |
| 2002 | 271 |
| 2003 | 299 |
| 2004 | 291 |
| 2005 | 281 |
| 2006 | 354 |
| 2007 | 328 |
| 2008 | 336 |
| 2009 | 234 |
| 2010 | 179 |
| 2011 | 118 |
| 2012 | 91 |
| 2013 | 95 |
| 2014 | 76 |
| 2015 | 36 |
| 2016 | 41 |
| 2017 | 38 |
| 2018 | 16 |
| 2019 | 15 |
| 2020 | 6 |
| 2021 | 2 |
| 2023 | 2 |
| 2024 | 1 |