The Hoover Index of Population Concentration: A Correction and Update

Geographers have made extensive use of the Hoover index to measure the evenness with which population is distributed across territorial units. This paper corrects an error in the original county-based series for the United States, presented by Duncan et al. In Statistical Geography (1961) and often reproduced. We extend the series backward and forward in time to show population deconcentration at the county level from at least 1890 until 1910 (as low-density areas grew rapidly), a second round of deconcentration corresponding to the nonmetropolitan turnaround of the 1970s, and a third, much weaker round beginning around 1990 along with a modest resurgence of nonmetropolitan population growth. When states are used as the basis for computing the index, deconcentration has been a consistent pattern, except for 1940 to 1970, and for this exception we offer an explanation. We attempt to put these findings in the context of long- and short-term patterns of metropolitanization.

Keywords::

• Hoover index
• population concentration
• population distribution