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Table 2.
Years for each phase of the different solar sunspot cycles.
| Minimum |
Increasing |
Maximum |
Decreasing |
|
|---|---|---|---|---|
| Phases of solar sunspot cycle | Rz < 20 | 20 ≤ Rz ≤ 100 | Rz > 100 | 100 ≥ Rz ≥ 20 |
| 20 | 1964 | 1966–1967 | 1968–1970 | 1971–1975 |
| 21 | 1976 | 1977–1978 | 1979–1982 | 1983–1985 |
| 22 | 1986 | 1987–1988 | 1989–1991 | 1992–1995 |
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