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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1955 | 1 |
| 1957 | 1 |
| 1958 | 2 |
| 1959 | 1 |
| 1961 | 1 |
| 1962 | 1 |
| 1965 | 1 |
| 1966 | 1 |
| 1969 | 2 |
| 1970 | 2 |
| 1972 | 2 |
| 1973 | 2 |
| 1974 | 4 |
| 1975 | 2 |
| 1976 | 1 |
| 1977 | 2 |
| 1978 | 3 |
| 1979 | 1 |
| 1980 | 3 |
| 1981 | 4 |
| 1983 | 3 |
| 1986 | 1 |
| 1987 | 1 |
| 1989 | 1 |
| 1991 | 2 |
| 1997 | 1 |
| 1998 | 2 |
| 1999 | 4 |
| 2007 | 1 |
| 2008 | 2 |
| 2009 | 1 |
| 2010 | 1 |
| 2011 | 1 |
| 2019 | 1 |
| 2020 | 1 |
| 2025 | 2 |
| 2026 | 1 |