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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1967 | 2 |
| 1968 | 7 |
| 1969 | 10 |
| 1970 | 3 |
| 1971 | 9 |
| 1972 | 14 |
| 1973 | 18 |
| 1974 | 18 |
| 1975 | 24 |
| 1976 | 21 |
| 1977 | 20 |
| 1978 | 28 |
| 1979 | 28 |
| 1980 | 31 |
| 1981 | 28 |
| 1982 | 40 |
| 1983 | 65 |
| 1984 | 59 |
| 1985 | 72 |
| 1986 | 73 |
| 1987 | 74 |
| 1988 | 77 |
| 1989 | 75 |
| 1990 | 70 |
| 1991 | 87 |
| 1992 | 95 |
| 1993 | 87 |
| 1994 | 91 |
| 1995 | 86 |
| 1996 | 65 |
| 1997 | 61 |
| 1998 | 88 |
| 1999 | 79 |
| 2000 | 84 |
| 2001 | 82 |
| 2002 | 83 |
| 2003 | 71 |
| 2004 | 92 |
| 2005 | 106 |
| 2006 | 126 |
| 2007 | 120 |
| 2008 | 100 |
| 2009 | 97 |
| 2010 | 114 |
| 2011 | 112 |
| 2012 | 110 |
| 2013 | 103 |
| 2014 | 105 |
| 2015 | 103 |
| 2016 | 100 |
| 2017 | 95 |
| 2018 | 106 |
| 2019 | 90 |
| 2020 | 69 |
| 2021 | 77 |
| 2022 | 65 |
| 2023 | 17 |