| Year | Confi. Interval | Confi. Level | Temperature (˚C) | Level | |
| From | To | ||||
| 1968 | (1965,1970) | 100% | 23.45 | 21.08 | |
| 1981 | (1980,1981) | 100% | 21.08 | 23.99 | |
| 1994 | (1993,1996) | 98% | 23.99 | 24.84 | |
| 2001 | (2000,2001) | 99% | 24.84 | 26.31 | |