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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1972 | 1 |
| 1975 | 1 |
| 1977 | 8 |
| 1978 | 9 |
| 1979 | 20 |
| 1980 | 24 |
| 1981 | 23 |
| 1982 | 32 |
| 1983 | 21 |
| 1984 | 24 |
| 1985 | 32 |
| 1986 | 20 |
| 1987 | 29 |
| 1988 | 26 |
| 1989 | 26 |
| 1990 | 40 |
| 1991 | 32 |
| 1992 | 50 |
| 1993 | 65 |
| 1994 | 51 |
| 1995 | 69 |
| 1996 | 67 |
| 1997 | 94 |
| 1998 | 82 |
| 1999 | 154 |
| 2000 | 231 |
| 2001 | 258 |
| 2002 | 327 |
| 2003 | 386 |
| 2004 | 411 |
| 2005 | 436 |
| 2006 | 378 |
| 2007 | 427 |
| 2008 | 525 |
| 2009 | 370 |
| 2010 | 429 |
| 2011 | 379 |
| 2012 | 377 |
| 2013 | 390 |
| 2014 | 349 |
| 2015 | 363 |
| 2016 | 342 |
| 2017 | 292 |
| 2018 | 370 |
| 2019 | 334 |
| 2020 | 281 |
| 2021 | 186 |
| 2022 | 27 |
| 2023 | 31 |
| 2024 | 49 |