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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1947 | 1 |
| 1948 | 1 |
| 1949 | 1 |
| 1950 | 9 |
| 1951 | 9 |
| 1952 | 6 |
| 1953 | 9 |
| 1954 | 10 |
| 1955 | 9 |
| 1956 | 8 |
| 1957 | 13 |
| 1958 | 7 |
| 1959 | 7 |
| 1960 | 11 |
| 1961 | 9 |
| 1962 | 4 |
| 1963 | 7 |
| 1964 | 7 |
| 1965 | 3 |
| 1968 | 2 |
| 1969 | 1 |
| 1970 | 4 |
| 1971 | 7 |
| 1972 | 51 |
| 1973 | 130 |
| 1974 | 181 |
| 1975 | 147 |
| 1976 | 164 |
| 1977 | 169 |
| 1978 | 178 |
| 1979 | 149 |
| 1980 | 150 |
| 1981 | 118 |
| 1982 | 166 |
| 1983 | 142 |
| 1984 | 184 |
| 1985 | 183 |
| 1986 | 176 |
| 1987 | 175 |
| 1988 | 182 |
| 1989 | 201 |
| 1990 | 227 |
| 1991 | 175 |
| 1992 | 159 |
| 1993 | 186 |
| 1994 | 150 |
| 1995 | 164 |
| 1996 | 183 |
| 1997 | 170 |
| 1998 | 154 |
| 1999 | 153 |
| 2000 | 130 |
| 2001 | 143 |
| 2002 | 116 |
| 2003 | 125 |
| 2004 | 106 |
| 2005 | 114 |
| 2006 | 110 |
| 2007 | 126 |
| 2008 | 123 |
| 2009 | 99 |
| 2010 | 81 |
| 2011 | 81 |
| 2012 | 83 |
| 2013 | 70 |
| 2014 | 77 |
| 2015 | 70 |
| 2016 | 66 |
| 2017 | 58 |
| 2018 | 63 |
| 2019 | 65 |
| 2020 | 45 |
| 2021 | 35 |
| 2022 | 27 |
| 2023 | 28 |
| 2024 | 12 |