The Urban Mortality Transition and Poor-Country Urbanization

Abstract

Today, the world’s fastest-growing cities lie in low-income countries, unlike the historical norm. Also, unlike the “killer cities” of history, cities in low-income countries grow not just through in-migration but also through their own natural increase. First, we use novel historical data to document that many poor countries urbanized at the same time as the postwar urban mortality transition. Second, we develop a framework incorporating location choice with heterogeneity in demographics and congestion costs across locations to account for this. In the framework, people prefer to live in low-mortality locations, and the aggregate rate of population growth and the locational choice of individuals interact. Third, we calibrate this to data from a sample of poor countries and find that informal urban areas (e.g., slums) can absorb additional population more easily than other locations. We show that between 1950 and 2005 the urban mortality transition could have doubled the urbanization rate as well as the size of informal urban areas in this sample. Of these effects, one-third could be attributed to the amenity effect of lower urban mortality rates, while the remainder is due to higher population growth disproportionately pushing people into informal urban areas. Fourth, simulations suggest that family planning programs, as well as industrialization or urban infrastructure and institutions may be effective in slowing poor-country urbanization. (JEL I12, J11, N30, O15, O18, R11, R23)

What is different about urbanization in rich and poor countries? Cities in Brazil, China, India and the United States

“…It is also possible that the surveyors may have undercounted many of the residents living in urban slums. Jedwab and Vollrath (2016) document that urban growth in India and…”

Measuring the size and growth of cities using nighttime light

“…On the other hand, the relatively high levels of density in developing regions may be a reflection of the recent, accelerated and informal urbanization process, experienced by these regions in the mid-twentieth century. In fact, much of the high density of developing cities is explained by the incidence of informal settlements (Jedwab & Vollrath 2017).…”

Pandemics, Places, and Populations: Evidence from the Black Death

“…Their rate of natural increase would have needed to be above 30 per 1,000for natural increase to fully explain recovery. These rates were unheard of until the 20th century, particularly in preindustrial cities where such rates were typically nil or negative (Woods, 2003;Voigtländer and Voth, 2013b;Jedwab and Vollrath, 2019).…”

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