Subcounty Data: Cautions and Recommendations
Need data for areas smaller than your county? IECAM has early childhood service and demographic data available on the zip code, township, elementary/unit school district, Chicago Community Area (CCA), and municipality levels.
However, you need to be careful because these smaller areas often do not fit nicely within the boundaries of other geographic areas.
Cautions
This multilayered image shows that geographic areas for school districts, zip codes, and counties, for example, often do not share boundaries. The lack of consistently common boundaries among these geographic regions, and others, can create challenges in understanding data at different scales.
Note that the Unit School District 46 (in yellow) is in three counties and encompasses parts (but not all) of more than a dozen zip codes.
Recommendations
- Need to break down your county into smaller units but stay within county boundaries? Try selecting "Township" as a region because township boundaries do not extend into neighboring counties. You can find an interactive map of Illinois townships on our Townships data description page.
- Census tracts can also be used to zoom in to the neighborhood level, and, like townships, they do not cross into another county. While IECAM does not provide data on the census tract level on its websites, IECAM staff can respond to census tract data requests via our online form.