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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1963 | 1 |
| 1964 | 14 |
| 1965 | 47 |
| 1966 | 87 |
| 1967 | 125 |
| 1968 | 158 |
| 1969 | 183 |
| 1970 | 231 |
| 1971 | 241 |
| 1972 | 228 |
| 1973 | 294 |
| 1974 | 321 |
| 1975 | 256 |
| 1976 | 211 |
| 1977 | 213 |
| 1978 | 186 |
| 1979 | 232 |
| 1980 | 189 |
| 1981 | 216 |
| 1982 | 203 |
| 1983 | 225 |
| 1984 | 192 |
| 1985 | 190 |
| 1986 | 180 |
| 1987 | 169 |
| 1988 | 159 |
| 1989 | 154 |
| 1990 | 157 |
| 1991 | 140 |
| 1992 | 149 |
| 1993 | 146 |
| 1994 | 123 |
| 1995 | 136 |
| 1996 | 123 |
| 1997 | 103 |
| 1998 | 129 |
| 1999 | 120 |
| 2000 | 94 |
| 2001 | 97 |
| 2002 | 119 |
| 2003 | 89 |
| 2004 | 118 |
| 2005 | 108 |
| 2006 | 105 |
| 2007 | 128 |
| 2008 | 115 |
| 2009 | 114 |
| 2010 | 122 |
| 2011 | 110 |
| 2012 | 107 |
| 2013 | 107 |
| 2014 | 88 |
| 2015 | 72 |
| 2016 | 91 |
| 2017 | 74 |
| 2018 | 66 |
| 2019 | 57 |
| 2020 | 55 |
| 2021 | 68 |
| 2022 | 46 |
| 2023 | 9 |