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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1963 | 1 |
| 1965 | 16 |
| 1966 | 64 |
| 1967 | 65 |
| 1968 | 71 |
| 1969 | 61 |
| 1970 | 83 |
| 1971 | 87 |
| 1972 | 84 |
| 1973 | 92 |
| 1974 | 83 |
| 1975 | 82 |
| 1976 | 101 |
| 1977 | 94 |
| 1978 | 84 |
| 1979 | 91 |
| 1980 | 67 |
| 1981 | 66 |
| 1982 | 70 |
| 1983 | 88 |
| 1984 | 134 |
| 1985 | 141 |
| 1986 | 155 |
| 1987 | 180 |
| 1988 | 164 |
| 1989 | 161 |
| 1990 | 140 |
| 1991 | 137 |
| 1992 | 142 |
| 1993 | 147 |
| 1994 | 117 |
| 1995 | 123 |
| 1996 | 77 |
| 1997 | 78 |
| 1998 | 78 |
| 1999 | 65 |
| 2000 | 67 |
| 2001 | 47 |
| 2002 | 48 |
| 2003 | 54 |
| 2004 | 50 |
| 2005 | 40 |
| 2006 | 49 |
| 2007 | 42 |
| 2008 | 48 |
| 2009 | 33 |
| 2010 | 39 |
| 2011 | 35 |
| 2012 | 38 |
| 2013 | 27 |
| 2014 | 27 |
| 2015 | 27 |
| 2016 | 30 |
| 2017 | 34 |
| 2018 | 25 |
| 2019 | 26 |
| 2020 | 20 |
| 2021 | 15 |
| 2024 | 0 |