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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1956 | 1 |
| 1961 | 1 |
| 1962 | 1 |
| 1963 | 3 |
| 1964 | 6 |
| 1965 | 7 |
| 1966 | 18 |
| 1967 | 112 |
| 1968 | 264 |
| 1969 | 303 |
| 1970 | 357 |
| 1971 | 515 |
| 1972 | 583 |
| 1973 | 508 |
| 1974 | 859 |
| 1975 | 841 |
| 1976 | 700 |
| 1977 | 367 |
| 1978 | 427 |
| 1979 | 516 |
| 1980 | 431 |
| 1981 | 353 |
| 1982 | 321 |
| 1983 | 210 |
| 1984 | 241 |
| 1985 | 249 |
| 1986 | 210 |
| 1987 | 207 |
| 1988 | 223 |
| 1989 | 193 |
| 1990 | 238 |
| 1991 | 193 |
| 1992 | 216 |
| 1993 | 212 |
| 1994 | 145 |
| 1995 | 244 |
| 1996 | 217 |
| 1997 | 239 |
| 1998 | 314 |
| 1999 | 396 |
| 2000 | 373 |
| 2001 | 472 |
| 2002 | 558 |
| 2003 | 531 |
| 2004 | 332 |
| 2005 | 198 |
| 2006 | 154 |
| 2007 | 155 |
| 2008 | 124 |
| 2009 | 104 |
| 2010 | 117 |
| 2011 | 146 |
| 2012 | 120 |
| 2013 | 59 |
| 2014 | 14 |
| 2015 | 16 |
| 2016 | 17 |
| 2017 | 16 |
| 2018 | 8 |
| 2019 | 9 |
| 2020 | 9 |
| 2021 | 17 |
| 2022 | 17 |
| 2023 | 1 |
| 2024 | 2 |