min Jan | max Jan | min Feb | max Feb | min Mar | max Mar | |
1948-58 | 20 | 25 | 20 | 27 | 17 | 25 |
1958-68 | 17 | 25 | 15 | 25 | 8 | 25 |
1968-78 | 17 | 22 | 18 | 25 | 15 | 25 |
1978-88 | 19 | 23 | 18 | 24 | 15 | 25 |
1988-98 | 18 | 23 | 17 | 24 | 15 | 23 |
1998-2008 | 19 | 22 | 17 | 23 | 18 | 23 |
2008-2014 | 20 | 23 | 17 | 23 | 20 | 25 |