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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1960 | 1 |
| 1964 | 2 |
| 1965 | 4 |
| 1966 | 2 |
| 1967 | 27 |
| 1968 | 67 |
| 1969 | 122 |
| 1970 | 145 |
| 1971 | 210 |
| 1972 | 239 |
| 1973 | 272 |
| 1974 | 284 |
| 1975 | 310 |
| 1976 | 284 |
| 1977 | 321 |
| 1978 | 386 |
| 1979 | 385 |
| 1980 | 418 |
| 1981 | 393 |
| 1982 | 402 |
| 1983 | 332 |
| 1984 | 314 |
| 1985 | 195 |
| 1986 | 188 |
| 1987 | 187 |
| 1988 | 217 |
| 1989 | 151 |
| 1990 | 186 |
| 1991 | 180 |
| 1992 | 149 |
| 1993 | 133 |
| 1994 | 101 |
| 1995 | 94 |
| 1996 | 83 |
| 1997 | 76 |
| 1998 | 55 |
| 1999 | 44 |
| 2000 | 40 |
| 2001 | 50 |
| 2002 | 54 |
| 2003 | 43 |
| 2004 | 48 |
| 2005 | 35 |
| 2006 | 44 |
| 2007 | 39 |
| 2008 | 35 |
| 2009 | 34 |
| 2010 | 45 |
| 2011 | 38 |
| 2012 | 22 |
| 2013 | 30 |
| 2014 | 24 |
| 2015 | 19 |
| 2016 | 17 |
| 2017 | 21 |
| 2018 | 18 |
| 2019 | 13 |
| 2020 | 10 |
| 2021 | 7 |
| 2022 | 1 |
| 2024 | 1 |