The Hoover Index is the most widely used measure for assessing the concentration or deconcentration tendencies of a country’s evolving population distribution. In this article, the authors propose alternative variants of the index designed to explore the influences of the various demographic components of change (birth, deaths, net domestic, and net international migration) on settlement dynamics. These decompositions can also be applied to examine the differential contributions of various race and ethnicity groups to overall trends. Using U.S. Census Bureau county population estimates, the authors deploy their approaches to examine the nature of deconcentration trends evidenced for the decadal periods 1990–1999 and 2000–2009.