Small-area population forecasts are used for a wide variety of planning and budgeting purposes. Using 1970 to 2005 data for incorporated places and unincorporated areas in Florida, we evaluate the accuracy of forecasts made with several extrapolation techniques, averages, and composite methods, and we assess the effects of differences in population size, growth rate, and length of forecast horizon on forecast errors. We further investigate the impact of adjusting forecasts to account for changes in special populations and annexations. The findings presented in this study will help practitioners make informed decisions when they construct and analyze small-area population forecasts.
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