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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1947 | 8 |
| 1948 | 1 |
| 1958 | 1 |
| 1959 | 1 |
| 1960 | 8 |
| 1961 | 1 |
| 1962 | 3 |
| 1963 | 10 |
| 1964 | 8 |
| 1965 | 20 |
| 1966 | 8 |
| 1967 | 31 |
| 1968 | 22 |
| 1969 | 34 |
| 1970 | 15 |
| 1971 | 10 |
| 1972 | 8 |
| 1973 | 2 |
| 1974 | 2 |
| 1975 | 1 |
| 1976 | 1 |
| 1977 | 1 |
| 1978 | 2 |
| 1980 | 1 |
| 1982 | 1 |
| 1985 | 1 |
| 1986 | 2 |
| 1987 | 1 |
| 1989 | 1 |
| 1998 | 1 |
| 2004 | 1 |
| 2005 | 1 |
| 2006 | 4 |
| 2007 | 1 |
| 2008 | 3 |
| 2009 | 1 |
| 2011 | 3 |
| 2012 | 1 |
| 2013 | 2 |
| 2015 | 2 |
| 2016 | 2 |
| 2017 | 1 |
| 2018 | 1 |
| 2020 | 1 |
| 2021 | 1 |
| 2024 | 1 |