Study Figure 2, a table showing the percentage of the population living in urban areas in selected world regions from 1970 to 2050.
Figure 2: Level of urbanisation (percentage of population living in urban areas) by region, 1970–2050
| Region | 1970 (%) | 2000 (%) | 2030 (Projected, %) | 2050 (Projected, %) |
|---|---|---|---|---|
| Sub-Saharan Africa | 15 | 30 | 45 | 60 |
| South Asia | 20 | 28 | 40 | 52 |
| North America | 72 | 79 | 84 | 88 |
| Europe | 63 | 70 | 78 | 83 |
Suggest one reason for a trend shown in Figure 2.
