
| Month | WS 1 | WS 2 | WS 3 | WS 4 | WS 5 | WS 6 |
| Jan | 5.9 | 7.2 | 8.4 | 8.2 | 8.7 | |
| Feb | 5.6 | 6.4 | 7.8 | 7.7 | 8.0 | |
| Mar | 6.5 | 5.7 | 8.7 | 8.7 | 9.0 | |
| Apr | ||||||
| May | 5.8 | 7.2 | 8.0 | 8.0 | ||
| Jun | ||||||
| Jul | ||||||
| Aug | ||||||
| Sep | 7.9 | 6.7 | 7.3 | 7.3 | 7.6 | |
| Oct | 4.9 | 6.9 | 7.7 | 7.6 | 7.9 | |
| Nov | 5.5 | 7.2 | 7.9 | 7.9 | 8.2 | |
| Dec | 4.7 | 6.2 | 6.8 | 6.4 | 7.2 | |
| AVG | 5.5 | 6.7 | 7.8 | 7.7 | 8.1 |