Beginning with the estimates for 2005, data from the American Community Survey were used in the estimation procedure; all prior years used data from the Annual Social and Economic Supplements of the Current Population Survey.

There is uncertainty associated with all estimates in this program. Where possible, we quantify this uncertainty through confidence intervals (please see a basic explanation of confidence intervals). For detail on the sources of uncertainty for state and county estimates, please see Quantifying Uncertainty for State and County Estimates. For a discussion of estimating the relative magnitude of this uncertainty in SAIPE school districts estimates, please see Quantifying Relative Error in School District Estimates.

Before attempting to compare estimates, please see the General Cautions page.