Revisiting the urbanization curve

Abstract

The urbanization process creates demographic landscapes that are both volatile and uneven. As regions or nations pursue economic development, the level of urbanization—the percentage share of people living in cities—follows a typical pattern: urban shares first rise slowly, then rapidly, and then slowly again. The entire sequence traces out an S-shaped figure often called the urbanization curve. This curve has been widely invoked in the discussion of Homo Urbanus but has rarely been used to analyze the urbanization experiences of different regions and nations. This paper revisits the urbanization curve and shows that national urbanization—whether contemporary or historical—generally conforms to the logistic process. Using UN population data, comparisons are made between the logistic model and other simple time-series and econometric models. The logistic process is sufficiently flexible to depict urbanization unfolding across nations at very different stages of economic development. The substantial variety now seen in national urbanization suggests the existence of separate urbanization clubs.