SAIPE revises and improves our methodology as time and resources allow. The details of the methodology differ slightly from year to year. The most significant change was between 2004 and 2005, when SAIPE began using data from the American Community Survey, rather than from the Annual Social and Economic Supplement to the Current Population Survey.
The SAIPE model has two distinct components:
School district estimates sum to county estimates, county estimates sum to state estimates, and state estimates sum to the national estimate.