This Population Data Booklet presents newly global and regional metropolitan trends among the United Nations Regional Groups. It also introduces the UN-Habitat Global Database of Metropolises.
Urban land expansion has surpassed urban population growth all over the world. Between 1990 and 2015, urban land expansion rates were almost double compared to urban population growth rates worldwide. Rates of 1.8 vs 1.2-fold and 3.9 vs 2.0-fold were reported in developed and developing countries respectively (UN-Habitat, 2016).
This phenomenon has been responsible for the rise of a new typology of cities, namely metropolises, also known as urban agglomerations, large coalesced cities, metropolitan areas, metropolitan zones, metropolitan regions, functional cities, megacities, among other names and definitions which vary depending on legal, administrative, political, economic or cultural criteria in the respective countries and regions. Although there is an ongoing debate on how to better define metropolises, most metropolitan authorities and experts agree that these areas share a common characteristic: they are all territories with multiple centralities which are connected rather than operating in isolation.