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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1947 | 2 |
| 1948 | 1 |
| 1949 | 1 |
| 1950 | 8 |
| 1951 | 3 |
| 1952 | 5 |
| 1953 | 1 |
| 1955 | 1 |
| 1956 | 3 |
| 1957 | 1 |
| 1958 | 1 |
| 1959 | 2 |
| 1960 | 3 |
| 1961 | 2 |
| 1962 | 3 |
| 1963 | 3 |
| 1964 | 20 |
| 1965 | 20 |
| 1966 | 27 |
| 1967 | 27 |
| 1968 | 43 |
| 1969 | 61 |
| 1970 | 59 |
| 1971 | 47 |
| 1972 | 62 |
| 1973 | 84 |
| 1974 | 81 |
| 1975 | 83 |
| 1976 | 60 |
| 1977 | 79 |
| 1978 | 98 |
| 1979 | 117 |
| 1980 | 106 |
| 1981 | 114 |
| 1982 | 122 |
| 1983 | 131 |
| 1984 | 118 |
| 1985 | 145 |
| 1986 | 133 |
| 1987 | 115 |
| 1988 | 122 |
| 1989 | 143 |
| 1990 | 119 |
| 1991 | 122 |
| 1992 | 88 |
| 1993 | 101 |
| 1994 | 101 |
| 1995 | 79 |
| 1996 | 75 |
| 1997 | 68 |
| 1998 | 63 |
| 1999 | 70 |
| 2000 | 71 |
| 2001 | 71 |
| 2002 | 53 |
| 2003 | 55 |
| 2004 | 62 |
| 2005 | 62 |
| 2006 | 63 |
| 2007 | 45 |
| 2008 | 45 |
| 2009 | 78 |
| 2010 | 53 |
| 2011 | 61 |
| 2012 | 65 |
| 2013 | 38 |
| 2014 | 47 |
| 2015 | 54 |
| 2016 | 50 |
| 2017 | 45 |
| 2018 | 36 |
| 2019 | 34 |
| 2020 | 30 |
| 2021 | 11 |
| 2022 | 15 |
| 2023 | 6 |
| 2024 | 4 |