Population forecasts for subcounty areas are used for a wide variety of planning and budgeting purposes. Given the importance of many of these uses, it is essential to investigate which techniques and procedures produce the most accurate forecasts. In this report, we describe several simple trend extrapolation techniques and several averages and composite methods based on those techniques. We evaluate the precision and bias of forecasts derived from these techniques using data from 1970–2005 for subcounty areas in Florida. We also evaluate the effects of differences in population size, growth rate, length of base period, and length of forecast horizon on forecast errors, and investigate the impact of adjusting forecasts to account for the effects of annexations and changes in institutional populations. We believe the findings presented in this report will help practitioners make informed decisions when they construct population forecasts for subcounty areas.

(Accompanying tables begin on page 34 of this report.)