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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 1 |
| 1960 | 2 |
| 1961 | 2 |
| 1962 | 4 |
| 1965 | 1 |
| 1966 | 1 |
| 1967 | 6 |
| 1968 | 12 |
| 1969 | 13 |
| 1970 | 13 |
| 1971 | 4 |
| 1972 | 17 |
| 1973 | 13 |
| 1974 | 17 |
| 1975 | 21 |
| 1976 | 24 |
| 1977 | 15 |
| 1978 | 37 |
| 1979 | 32 |
| 1980 | 29 |
| 1981 | 33 |
| 1982 | 53 |
| 1983 | 39 |
| 1984 | 39 |
| 1985 | 47 |
| 1986 | 49 |
| 1987 | 36 |
| 1988 | 34 |
| 1989 | 58 |
| 1990 | 9 |
| 1991 | 12 |
| 1992 | 47 |
| 1993 | 134 |
| 1994 | 177 |
| 1995 | 211 |
| 1996 | 264 |
| 1997 | 286 |
| 1998 | 258 |
| 1999 | 263 |
| 2000 | 275 |
| 2001 | 240 |
| 2002 | 278 |
| 2003 | 318 |
| 2004 | 307 |
| 2005 | 370 |
| 2006 | 367 |
| 2007 | 405 |
| 2008 | 420 |
| 2009 | 448 |
| 2010 | 436 |
| 2011 | 454 |
| 2012 | 482 |
| 2013 | 499 |
| 2014 | 508 |
| 2015 | 507 |
| 2016 | 378 |
| 2017 | 339 |
| 2018 | 294 |
| 2019 | 273 |
| 2020 | 210 |
| 2021 | 128 |
| 2022 | 21 |
| 2023 | 15 |
| 2024 | 55 |