A Spatial Decomposition of County Population Growth in the United States: Population Redistribution in the Rural-to-Urban Continuum, 1980–2010

Abstract

A significant theme in demographic studies has been the population redistribution patterns among metropolitan centers, non-metropolitan areas surrounding them, and the so-called hinterlands beyond. Virtually all of this research has used the traditional metropolitan vs. non-metropolitan classification scheme. However, this classification system has a number of inherent flaws concerning the identification of rural and urban areas. Our previous research, for instance, has shown that metro areas are highly heterogeneous in terms of characteristics typifying “rural” and “urban” (Porter and Howell 2009). This study aims to partially alleviate the problem through the implementation of a new sub-county geography, the Non-Place Territory (NPT) combined with a spatial decomposition method for combining county and place-level data. The NPT is simply the balance of the county not designated as a census place or, in other words, the local expression of “out in the county”. Through the use of this geography and population data from the U.S. Census Bureau, we spatially decompose population growth in the U.S at the sub-county level using 1980, 1990, 2000, and 2010 census population data applied to a unified place vs. non-place territory GIS coverage. Through the application of exploratory spatial data analysis procedures, we identify sub-county patterns of population distribution and redistribution over the three decades of interest. The results identify statistically significant pockets of growth, stability, and decline within counties across metropolitan and non-metropolitan localities. This approach and these results pave the way for a more contextual understanding of population redistribution in the U.S.