Chicago Community Areas
DRAFT: DO NOT QUOTE
Community Areas in Chicago were first delineated in the late 1920s by
the Social Science Research Committee at the University of Chicago.
At that time they defined 75 Community Areas, using criteria designed to
identify areas with separate histories and community awareness. Even
at that time these subarea definitions had shortcomings, including
the need to define the Community Areas in terms of full census tracts.
The boundaries have not been revised to reflect change in these areas,
but instead have been kept relatively stable to allow comparisons of
the areas over time. (Minor changes in the original areas have
occurred due to annexations and minor changes in census tract
boundaries). Two new Community Areas have been defined since that
time. Area 76, Ohare, was defined to incorporate Ohare Airport
and surrounding areas when the City of Chicago annexed that area.
Area 77, Edgewater, was split from Area 3 (Uptown) by the City of
Chicago before 1980 data were analyzed.
Aggregating from Census Tract data
The Community Area data here is aggregated from STF3 Census Tract Data.
In general the first two digits of each Census Tract in Chicago refer to the Community Area number.
So tract number 0101 is in Community Area 01 (Rogers Park).
The exceptions to this rule are the relatively recently defined 76, 77 and the redefined 03.
Community Area 77, (Edgewater, formerly part of 03, Uptown) is made up of tracts 0301-0309, while tracts 0310-0321 remain Uptown.
Community Area 76 (Ohare) is the only Community Area containing partial tracts (Census Tracts partially in the City of Chicago, partially in the suburbs).
All the Chicago portionsof tracts with numbers starting 76 or higher, and with population, are part of Community Area 76.
(there are tracts with numbers higher than 76 not in Ohare, the Chicago portion of tract 8209 for example, but there are no people in the Chicago portions of these tracts).