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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1960 | 52 |
| 1961 | 55 |
| 1962 | 66 |
| 1963 | 59 |
| 1964 | 113 |
| 1965 | 101 |
| 1966 | 114 |
| 1967 | 105 |
| 1968 | 173 |
| 1969 | 296 |
| 1970 | 239 |
| 1971 | 225 |
| 1972 | 244 |
| 1973 | 269 |
| 1974 | 277 |
| 1975 | 317 |
| 1976 | 221 |
| 1977 | 168 |
| 1978 | 189 |
| 1979 | 171 |
| 1980 | 180 |
| 1981 | 167 |
| 1982 | 171 |
| 1983 | 193 |
| 1984 | 224 |
| 1985 | 242 |
| 1986 | 284 |
| 1987 | 358 |
| 1988 | 309 |
| 1989 | 334 |
| 1990 | 350 |
| 1991 | 388 |
| 1992 | 388 |
| 1993 | 455 |
| 1994 | 458 |
| 1995 | 408 |
| 1996 | 396 |
| 1997 | 377 |
| 1998 | 417 |
| 1999 | 415 |
| 2000 | 420 |
| 2001 | 383 |
| 2002 | 459 |
| 2003 | 420 |
| 2004 | 416 |
| 2005 | 552 |
| 2006 | 557 |
| 2007 | 479 |
| 2008 | 429 |
| 2009 | 364 |
| 2010 | 440 |
| 2011 | 480 |
| 2012 | 499 |
| 2013 | 471 |
| 2014 | 515 |
| 2015 | 521 |
| 2016 | 520 |
| 2017 | 535 |
| 2018 | 502 |
| 2019 | 508 |
| 2020 | 628 |
| 2021 | 572 |
| 2022 | 508 |
| 2023 | 73 |