More Evidence for the 'New Donut' Model of Metropolitan Areas

The riots in Ferguson, MO brought mainstream media attention to a phenomenon that has been happening slowly for the last two decades. The old conception of cities as poor, minority-dominated slums surrounded by affluent suburbs has ceased to be an accurate description for most cities. Instead, revitalized urban centers are surging in popularity.

This doesn’t signal abandonment of the suburbs, however. Newer and larger suburbs continue to be built around major metropolitan areas, accounting for most of their population growth, and leaving an inner ring of less desirable older suburbs that will be the new centers of poverty and economic stagnation.

This story has been supported by anecdotal evidence across the country, but researchers have thus far failed to provide statistical evidence. Existing research centers on population growth, but this is an inaccurate gauge of the desirability and economic vitality of an area that has already been urbanized. In fact, a surge in popularity often attracts wealthier residents with smaller household sizes, which may reduce total population.

Instead, Luke Juday looks at income and education as an indicator of who lives in different zones. He looks at four major metropolitan areas: Charlotte, Atlanta, Denver, and Houston. Each is roughly geographically symmetrical and has a single clear city center, making them likely to represent the donut shape. They are also experiencing significant growth, have relatively low housing prices, and have few unique land use restrictions that might distort migration trends.

The results are striking. In 1990, each city had something close to a "hump" graph. Low rates of education and income in the city center gave way to high rates in the suburbs and then fell again in rural areas. Today, this has turned into an "S-curve," with high rates of education and income in the core, low rates several miles outside of it, and high rates in more distant suburbs.