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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 1 |
| 1965 | 13 |
| 1966 | 7 |
| 1967 | 15 |
| 1968 | 12 |
| 1969 | 28 |
| 1970 | 19 |
| 1971 | 21 |
| 1972 | 18 |
| 1973 | 29 |
| 1974 | 31 |
| 1975 | 27 |
| 1976 | 23 |
| 1977 | 41 |
| 1978 | 45 |
| 1979 | 46 |
| 1980 | 60 |
| 1981 | 38 |
| 1982 | 42 |
| 1983 | 41 |
| 1984 | 50 |
| 1985 | 59 |
| 1986 | 53 |
| 1987 | 70 |
| 1988 | 68 |
| 1989 | 68 |
| 1990 | 67 |
| 1991 | 73 |
| 1992 | 81 |
| 1993 | 79 |
| 1994 | 77 |
| 1995 | 95 |
| 1996 | 79 |
| 1997 | 96 |
| 1998 | 94 |
| 1999 | 95 |
| 2000 | 100 |
| 2001 | 98 |
| 2002 | 122 |
| 2003 | 132 |
| 2004 | 138 |
| 2005 | 137 |
| 2006 | 167 |
| 2007 | 147 |
| 2008 | 175 |
| 2009 | 146 |
| 2010 | 187 |
| 2011 | 219 |
| 2012 | 236 |
| 2013 | 237 |
| 2014 | 234 |
| 2015 | 224 |
| 2016 | 217 |
| 2017 | 237 |
| 2018 | 222 |
| 2019 | 179 |
| 2020 | 124 |
| 2021 | 61 |
| 2022 | 6 |
| 2023 | 2 |
| 2024 | 1 |