Rural to urban migration has been a typical phenomenon of the industrialization and modernization of societies. However, rural areas have been both regions of origin and regions of destination for migrants. In 2012, 47 percent of the global population still lived in rural areas, according to the World Bank. The share of rural population ­differs widely from 0 percent in the Hong Kong and Macao Special Administrative Regions, China, to 6 to 7 percent in Iceland and Argentina, to 80 percent and more in countries such as ­Cambodia, Nepal, and Burundi. Even the largest countries of the world still have a significant share of rural population, such as China (48 percent), India (68 percent), the Russian Federation (26 percent), and the United States (17 percent).

Rural ...