Source: United Nations, Department of Economic and Social Affairs, Population
Division (2006). World Urbanization Prospects: The 2005 Revision. New
York: United Nations.
World Urban Population, 1950-2005 with Projections to 2020 (in billions)
Between 1950 and 2005 the global urban population has more than tripled
to reach 3.15 billion. While urbanization has considerably slowed down
in developed countries, the developing world is where cities are growing
the most. It accounted for 68% of the urban population in 2000 and by
2020, 77% of the global urban population is expected to be in developed
countries. This process will be accompanied with significant surges
in urban mobility demands. On the other hand, mobility demands in urban
areas can be more efficiently satisfied with collective transportation
than mobility demands in rural areas.