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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 | 4 |
| 1951 | 1 |
| 1952 | 2 |
| 1954 | 1 |
| 1956 | 2 |
| 1957 | 3 |
| 1959 | 1 |
| 1961 | 1 |
| 1963 | 3 |
| 1964 | 1 |
| 1965 | 1 |
| 1967 | 1 |
| 1968 | 2 |
| 1969 | 3 |
| 1970 | 1 |
| 1971 | 6 |
| 1972 | 1 |
| 1973 | 4 |
| 1974 | 5 |
| 1975 | 2 |
| 1976 | 2 |
| 1977 | 2 |
| 1978 | 4 |
| 1979 | 1 |
| 1980 | 3 |
| 1981 | 5 |
| 1983 | 1 |
| 1984 | 3 |
| 1985 | 1 |
| 1986 | 3 |
| 1987 | 4 |
| 1994 | 1 |
| 2014 | 1 |
| 2016 | 2 |
| 2017 | 2 |
| 2019 | 3 |
| 2020 | 2 |
| 2021 | 1 |
| 2022 | 1 |
| 2024 | 0 |