Abstract
This paper analyzes the interrelationships of city size and growth in the American Midwest from 1940 to 1970 in an effort to synthesize the study of urban growth rates and of city-size distributions. Changes in the rank–size distribution are related to the differential growth of different-size urban places; some relationship in changes over time is evident, but there is little correspondence in static analyses. The urban system analyzed by various threshold sizes examines the sensitivity of rank–size coefficients and urban growth-rate stability to the threshold. The threshold size appears to be far more important than previous research has considered, and noticeably influences the analysis of urban growth rates and rank–size distributions.