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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 1 |
| 1965 | 1 |
| 1966 | 17 |
| 1967 | 19 |
| 1968 | 28 |
| 1969 | 44 |
| 1970 | 67 |
| 1971 | 81 |
| 1972 | 114 |
| 1973 | 123 |
| 1974 | 70 |
| 1975 | 51 |
| 1976 | 53 |
| 1977 | 53 |
| 1978 | 42 |
| 1979 | 64 |
| 1980 | 63 |
| 1981 | 38 |
| 1982 | 53 |
| 1983 | 79 |
| 1984 | 80 |
| 1985 | 79 |
| 1986 | 68 |
| 1987 | 85 |
| 1988 | 105 |
| 1989 | 94 |
| 1990 | 92 |
| 1991 | 77 |
| 1992 | 70 |
| 1993 | 67 |
| 1994 | 73 |
| 1995 | 105 |
| 1996 | 160 |
| 1997 | 144 |
| 1998 | 179 |
| 1999 | 176 |
| 2000 | 172 |
| 2001 | 191 |
| 2002 | 188 |
| 2003 | 208 |
| 2004 | 184 |
| 2005 | 217 |
| 2006 | 238 |
| 2007 | 243 |
| 2008 | 226 |
| 2009 | 225 |
| 2010 | 274 |
| 2011 | 334 |
| 2012 | 325 |
| 2013 | 331 |
| 2014 | 338 |
| 2015 | 392 |
| 2016 | 310 |
| 2017 | 317 |
| 2018 | 290 |
| 2019 | 255 |
| 2020 | 262 |
| 2021 | 147 |
| 2022 | 16 |
| 2023 | 12 |
| 2024 | 11 |