Epoch I | Epoch II | Epoch III | Epoch IV | Epoch V | Epoch VI | Epoch VII | Epoch VIII | |
Middle East | 4 | 4 | 4 | 4 | 4 | 3 | 3 | 4 |
North Africa | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
China | 3 | 4 | 5 | 6 | 5 | 5 | 6 | 7 |
India | 1 | 3 | 4 | 5 | 5 | 5 | 6 | 7 |
Southern Europe | 2 | 3 | 4 | 4 | 4 | 4 | 4 | 6 |
Northern Europe | 2 | 2 | 3 | 3 | 3 | 5 | 6 | 8 |
Southeast Asia | 1 | 1 | 1 | 2 | 3 | 3 | 4 | 5 |
Eurasia | 1 | 1 | 1 | 2 | 2 | 2 | 2 | 4 |
North America | 1 | 1 | 1 | 2 | 3 | 3 | 3 | 5 |
South America | 1 | 1 | 1 | 1 | 2 | 3 | 3 | 3 |
Subsaharan Africa | 1 | 1 | 1 | 2 | 3 | 3 | 4 | 5 |
Japan | 1 | 2 | 3 | 4 | 5 | |||
Australia | 1 | 1 |