University of Illinois Urbana‑Champaign


Data releases and methodology

Following the practice of the U.S. Census Bureau, each year IECAM demographers prepare a “data release” that includes the new data for the most recently available year plus updated data for the previous several years. Each year’s release is slightly more accurate than the previous year. The five-year span is based on IECAM’s use of the 5-year ACS (American Community Survey) as one of its principal demographic data sources. Data for a given year are released two years after the data year.