Components of Urban Growth for Large Urban Areas in the U.S., 1950-2010

Abstract

Urban growth refers to both increases in the population and number of housing units in an urban area and the spatial expansion of the urban area. The growth of urban areas is frequently attributed to the development of new housing units in rural areas on the urban fringe, resulting in those areas being added to the urban area. The total increases in housing units in 57 large urban areas from 1950 to 2010 are divided into 4 components, the percentages of that growth that is new development in rural areas that become urban, housing units already present in those rural areas, areas added to the urban areas that were already urban but were not included previously because they were not contiguous to the urban area, and increases in housing units within the existing urban area. On average the development of new units in rural areas constituted only a small fraction of urban housing unit growth, with increases in the existing urban area accounting for on average over half of that growth.