The Transition to a Predominantly Urban World and its Underpinnings
This paper describes the dramatic changes in the size of the world’s urban population and of its largest cities over the last 100 years. This includes the almost tenfold increase in the average size of the world’s 100 largest cities between 1900 and 2000. It also describes the changing distribution of cities between regions. In 1900, Europe had more than half the world’s 100 largest cities, now it has only 10. In 1900, Asia had 22 of the world’s 100 largest cities; now it has nearly half of them. But the paper also explains how and why the world is actually less urbanized and less dominated by large cities than expected and questions whether rapid urbanization will continue in Africa. The long-term trends in urban change in each region are discussed, as are the changes in the economic, social and political drivers – for instance the political changes associated with the ending of colonial empires and the achievement of independence and the economic changes associated with globalization. Today, the main driver of urban change is the geography of where profit-seeking enterprises choose to concentrate (or to avoid). This can be seen in the how the world’s largest economies have a high concentration of the world’s urban population and its largest cities. Also in how increases in levels of urbanization for most low- and middle-income nations over the last 50 years track increases in the proportion of GDP generated by industry and services and the proportion of the labour force working in these sectors.