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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1972 | 1 |
| 1975 | 2 |
| 1976 | 1 |
| 1986 | 2 |
| 1987 | 1 |
| 1988 | 2 |
| 1989 | 2 |
| 1992 | 2 |
| 1993 | 3 |
| 1994 | 6 |
| 1995 | 3 |
| 1996 | 6 |
| 1997 | 7 |
| 1998 | 8 |
| 1999 | 7 |
| 2000 | 20 |
| 2001 | 14 |
| 2002 | 22 |
| 2003 | 25 |
| 2004 | 22 |
| 2005 | 39 |
| 2006 | 42 |
| 2007 | 36 |
| 2008 | 49 |
| 2009 | 64 |
| 2010 | 97 |
| 2011 | 114 |
| 2012 | 92 |
| 2013 | 117 |
| 2014 | 121 |
| 2015 | 117 |
| 2016 | 155 |
| 2017 | 156 |
| 2018 | 194 |
| 2019 | 155 |
| 2020 | 150 |
| 2021 | 168 |
| 2022 | 147 |
| 2023 | 30 |