| Zones | January to April | May to June | July | August to September | October | November | December |
| Extreme North (EN) | |||||||
| 1 | 0.9 | 0.9 | 0.9 | 0.9 | 0.9 | 1 | |
| North (N) | 1 | 1+10%EN | 1 | 1 | 1 | 1+10%EN | 1 |
| Centre | 1 | 1 | 1+10%EN | 1 | 1+10%EN | 1 | 1 |
| South | 1 | 1 | 1 | 1+10%EN | 1 | 1 | 1 |