Culture of Congestion  

Latest Posts  |  Archive  | 

'The Evolution of City Population Density in the United States'

by Sandy Ikeda
Sun, 15 Jun 2008 at 3:09 AM

Print

Send

RSS

Share:

That's the title of an interesting paper by Kevin A. Bryan, Brian D. Minton, and Pierre-Daniel G. Sarte published by the Federal Reserve Bank of Richmond. You can find the article on this website, although you'll have to look for it a bit on the page. It gets a bit technical in places, but they present their results in straightforward diagrammatic form.

(Thanks to my colleague Bill Butos for the pointer.)

From the conclusion:

This article provides two novel contributions. First, it constructs an electronic data set of urban densities in the United States during the previous seven decades for three different definitions of a city. Second, it applies non- parametric techniques to estimate the distribution of those densities, and finds that there has been a stark decrease in density during the period studied. This deconcentration has been occurring continuously since at least 1940, in every area of the United States, and among both new and old cities.

Falling urban densities suggest that, over the past seven decades, the productivity benefits of dense cities have been weakening. Decreasing costs of transportation and communication have allowed firms to move production workers out of high-rent areas, and have allowed residents to move away from downtowns. It is unclear what effect these changes in the urban landscape will have on knowledge accumulation and growth in the future.

Still, a better understanding of this relation will be able to build on solid work like this.

One of the most useful parts of the paper comes at the beginning, which discusses the various ways to define a "city" for the purposes of studying population density — i.e., as a political entity, urbanized area, and metropolitan statistical area — and offers a critique of using the MSA as the denominator of a density ratio. Urban economists use these terms a lot and they're not always clearly explained, so this can be valuable for someone new to the area.

Culture of Congestion Homepage