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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1968 | 1 |
| 1969 | 1 |
| 1970 | 1 |
| 1972 | 9 |
| 1973 | 33 |
| 1974 | 51 |
| 1975 | 90 |
| 1976 | 65 |
| 1977 | 103 |
| 1978 | 55 |
| 1979 | 61 |
| 1980 | 63 |
| 1981 | 45 |
| 1982 | 70 |
| 1983 | 49 |
| 1984 | 54 |
| 1985 | 56 |
| 1986 | 60 |
| 1987 | 54 |
| 1988 | 56 |
| 1989 | 63 |
| 1990 | 59 |
| 1991 | 66 |
| 1992 | 88 |
| 1993 | 97 |
| 1994 | 92 |
| 1995 | 119 |
| 1996 | 108 |
| 1997 | 114 |
| 1998 | 178 |
| 1999 | 158 |
| 2000 | 150 |
| 2001 | 126 |
| 2002 | 126 |
| 2003 | 139 |
| 2004 | 87 |
| 2005 | 93 |
| 2006 | 99 |
| 2007 | 105 |
| 2008 | 81 |
| 2009 | 76 |
| 2010 | 87 |
| 2011 | 66 |
| 2012 | 89 |
| 2013 | 80 |
| 2014 | 100 |
| 2015 | 80 |
| 2016 | 68 |
| 2017 | 70 |
| 2018 | 60 |
| 2019 | 63 |
| 2020 | 55 |
| 2021 | 66 |
| 2022 | 50 |
| 2023 | 43 |
| 2024 | 19 |