Census Tract

A Census Tract is a small, relatively permanent statistical subdivision of a county delineated by the U.S. Census Bureau for tabulating and publishing demographic data. Designed to be relatively homogeneous in population characteristics, economic status, and living conditions, census tracts typically contain between 1,200 and 8,000 residents, with an optimum of 4,000. They are the most commonly used geographic unit for neighborhood-level demographic and socioeconomic analysis. Census tracts are delineated with local input to follow visible features like roads, rivers, and railroad tracks where possible. While designed to be stable over time for longitudinal comparison, tracts may be split when population growth makes them too large or merged when population decline makes them too small. The Census Bureau publishes tract boundaries as TIGER/Line shapefiles for GISGISGeographic Information Systems (GIS) enable users to analyze and visualize spatial data to uncover patterns, relation... use, and portals like data.census.gov provide downloadable demographic tables keyed to tract identifiers. Applications include Opportunity Zone designation that targets investment incentives to distressed tracts, Community Development Block Grant allocation, health outcome mapping that compares disease rates across neighborhoods, school quality analysis, and market segmentation that characterizes consumer demographics at the neighborhood level. Federal programs like the CDC Social Vulnerability Index and the EPA EJScreen tool use tract-level data to identify communities requiring targeted assistance.