| min Jul | max Jul | min Age | max Age | min Sep | max Sep | |
| 1948-58 | 50 | 54 | 50 | 55 | 52 | 55 |
| 1958-68 | 51 | 54 | 52 | 55 | 54 | 60 |
| 1968-78 | 50 | 56 | 53 | 58 | 56 | 57 |
| 1978-88 | 54 | 60 | 53 | 60 | 56 | 59 |
| 1988-98 | 51 | 59 | 54 | 57 | 55 | 61 |
| 1998-2008 | 41 | 53 | 52 | 54 | 50 | 54 |
| 2008-2014 | 48 | 51 | 50 | 53 | 53 | 54 |