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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1956 | 1 |
| 1957 | 1 |
| 1959 | 1 |
| 1961 | 2 |
| 1963 | 4 |
| 1964 | 3 |
| 1966 | 1 |
| 1967 | 1 |
| 1969 | 2 |
| 1970 | 2 |
| 1973 | 2 |
| 1974 | 1 |
| 1975 | 3 |
| 1976 | 2 |
| 1977 | 2 |
| 1979 | 1 |
| 1980 | 2 |
| 1981 | 4 |
| 1983 | 2 |
| 1984 | 2 |
| 1987 | 1 |
| 1990 | 2 |
| 1991 | 2 |
| 1992 | 2 |
| 1993 | 1 |
| 1995 | 1 |
| 1997 | 1 |
| 1998 | 1 |
| 2007 | 1 |
| 2008 | 1 |
| 2009 | 2 |
| 2010 | 1 |
| 2011 | 3 |
| 2012 | 1 |
| 2013 | 3 |
| 2014 | 3 |
| 2015 | 1 |
| 2016 | 4 |
| 2017 | 3 |
| 2019 | 1 |
| 2021 | 3 |
| 2022 | 1 |
| 2025 | 0 |