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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 5 |
| 1965 | 42 |
| 1966 | 86 |
| 1967 | 75 |
| 1968 | 123 |
| 1969 | 110 |
| 1970 | 148 |
| 1971 | 193 |
| 1972 | 247 |
| 1973 | 297 |
| 1974 | 281 |
| 1975 | 294 |
| 1976 | 275 |
| 1977 | 267 |
| 1978 | 221 |
| 1979 | 236 |
| 1980 | 161 |
| 1981 | 179 |
| 1982 | 93 |
| 1983 | 95 |
| 1984 | 89 |
| 1985 | 107 |
| 1986 | 83 |
| 1987 | 72 |
| 1988 | 113 |
| 1989 | 133 |
| 1990 | 112 |
| 1991 | 110 |
| 1992 | 136 |
| 1993 | 145 |
| 1994 | 175 |
| 1995 | 157 |
| 1996 | 145 |
| 1997 | 136 |
| 1998 | 105 |
| 1999 | 74 |
| 2000 | 82 |
| 2001 | 106 |
| 2002 | 83 |
| 2003 | 99 |
| 2004 | 87 |
| 2005 | 70 |
| 2006 | 97 |
| 2007 | 84 |
| 2008 | 86 |
| 2009 | 69 |
| 2010 | 54 |
| 2011 | 53 |
| 2012 | 52 |
| 2013 | 35 |
| 2014 | 34 |
| 2015 | 27 |
| 2016 | 27 |
| 2017 | 30 |
| 2018 | 33 |
| 2019 | 19 |
| 2020 | 15 |
| 2021 | 19 |
| 2022 | 4 |
| 2024 | 3 |