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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1968 | 21 |
| 1969 | 33 |
| 1970 | 54 |
| 1971 | 70 |
| 1972 | 72 |
| 1973 | 67 |
| 1974 | 111 |
| 1975 | 132 |
| 1976 | 136 |
| 1977 | 151 |
| 1978 | 180 |
| 1979 | 233 |
| 1980 | 212 |
| 1981 | 277 |
| 1982 | 259 |
| 1983 | 320 |
| 1984 | 291 |
| 1985 | 284 |
| 1986 | 298 |
| 1987 | 332 |
| 1988 | 298 |
| 1989 | 339 |
| 1990 | 294 |
| 1991 | 297 |
| 1992 | 333 |
| 1993 | 335 |
| 1994 | 237 |
| 1995 | 261 |
| 1996 | 324 |
| 1997 | 291 |
| 1998 | 333 |
| 1999 | 268 |
| 2000 | 272 |
| 2001 | 284 |
| 2002 | 338 |
| 2003 | 378 |
| 2004 | 389 |
| 2005 | 419 |
| 2006 | 379 |
| 2007 | 383 |
| 2008 | 381 |
| 2009 | 355 |
| 2010 | 444 |
| 2011 | 476 |
| 2012 | 488 |
| 2013 | 454 |
| 2014 | 447 |
| 2015 | 418 |
| 2016 | 378 |
| 2017 | 309 |
| 2018 | 338 |
| 2019 | 295 |
| 2020 | 253 |
| 2021 | 290 |
| 2022 | 240 |
| 2023 | 83 |