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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1948 | 1 |
| 1957 | 10 |
| 1958 | 25 |
| 1959 | 20 |
| 1963 | 6 |
| 1964 | 11 |
| 1965 | 34 |
| 1966 | 53 |
| 1967 | 62 |
| 1968 | 55 |
| 1969 | 80 |
| 1970 | 79 |
| 1971 | 44 |
| 1972 | 45 |
| 1973 | 25 |
| 1974 | 25 |
| 1975 | 33 |
| 1976 | 24 |
| 1977 | 27 |
| 1978 | 50 |
| 1979 | 32 |
| 1980 | 39 |
| 1981 | 39 |
| 1982 | 52 |
| 1983 | 57 |
| 1984 | 60 |
| 1985 | 66 |
| 1986 | 60 |
| 1987 | 79 |
| 1988 | 66 |
| 1989 | 96 |
| 1990 | 78 |
| 1991 | 102 |
| 1992 | 122 |
| 1993 | 117 |
| 1994 | 123 |
| 1995 | 109 |
| 1996 | 131 |
| 1997 | 116 |
| 1998 | 96 |
| 1999 | 107 |
| 2000 | 102 |
| 2001 | 80 |
| 2002 | 71 |
| 2003 | 69 |
| 2004 | 73 |
| 2005 | 78 |
| 2006 | 80 |
| 2007 | 89 |
| 2008 | 73 |
| 2009 | 79 |
| 2010 | 73 |
| 2011 | 81 |
| 2012 | 93 |
| 2013 | 102 |
| 2014 | 90 |
| 2015 | 97 |
| 2016 | 115 |
| 2017 | 91 |
| 2018 | 81 |
| 2019 | 50 |
| 2020 | 52 |
| 2021 | 32 |
| 2022 | 4 |
| 2024 | 4 |