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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1968 | 1 |
| 1969 | 2 |
| 1970 | 2 |
| 1971 | 1 |
| 1972 | 4 |
| 1973 | 8 |
| 1974 | 7 |
| 1975 | 8 |
| 1976 | 8 |
| 1977 | 9 |
| 1978 | 16 |
| 1979 | 12 |
| 1980 | 14 |
| 1981 | 8 |
| 1982 | 11 |
| 1983 | 18 |
| 1984 | 16 |
| 1985 | 24 |
| 1986 | 21 |
| 1987 | 17 |
| 1988 | 36 |
| 1989 | 58 |
| 1990 | 96 |
| 1991 | 157 |
| 1992 | 295 |
| 1993 | 354 |
| 1994 | 392 |
| 1995 | 502 |
| 1996 | 607 |
| 1997 | 837 |
| 1998 | 1016 |
| 1999 | 1284 |
| 2000 | 2103 |
| 2001 | 1935 |
| 2002 | 2157 |
| 2003 | 2465 |
| 2004 | 2611 |
| 2005 | 3034 |
| 2006 | 3412 |
| 2007 | 3890 |
| 2008 | 4213 |
| 2009 | 4581 |
| 2010 | 5312 |
| 2011 | 5944 |
| 2012 | 6929 |
| 2013 | 7758 |
| 2014 | 8598 |
| 2015 | 9352 |
| 2016 | 10116 |
| 2017 | 10846 |
| 2018 | 11807 |
| 2019 | 13020 |
| 2020 | 15845 |
| 2021 | 18876 |
| 2022 | 19416 |
| 2023 | 5107 |