The Parcel 2000 feature contains tax parcel polygons for the 2000 property tax assessment at the County. This feature reflects tax parcel polygons as they existed from 1/1/2000 through 12/31/2000. Each parcel is uniquely identified with a Property Index Number (PIN).

The Parcel 2001 feature contains tax parcel polygons for the 2001 property tax assessment at the County. This feature reflects tax parcel polygons as they existed from 1/1/2001 through 12/31/2001. Each parcel is uniquely identified with a Property Index Number (PIN).

The Parcel 2002 feature contains tax parcel polygons for the 2002 property tax assessment at the County. This feature reflects tax parcel polygons as they existed from 1/1/2002 through 12/31/2002. Each parcel is uniquely identified with a Property Index Number (PIN).

Updated 10/14/2011, use for mapping

Enclosed data represents outpatient registrations including hospital ancillary services (e.g. laboratory, radiology, physical therapy, dialysis), primary and speciality care clinics (Fantus, Stroger Speciality Clinic, Ambulatory Screening Center, Prieto, Austin, Logan Square, Cicero, Vista, Child Advocacy Center, Woodlawn Adult Clinic, Englewood, Morton East, Near South, Sengstacke, Southside Pediatrics, Southside OB, Cottage Grove, Lincoln Robbins, Woody Winston, and OFH Speciality Clinic) same day surgery, CORE center and emergency department registrations.

2,330 of 2009 and 3,093 of 2008 zip code registrations are not included in this data file due to privacy concerns when 10 registrations or less occurred per zip code

2010 U.S. Census Mail Return Rates and Demographics by Tract for Cook County. According to the US Census, tracts that fell below the 73% threshold were designated as containing "hard-to-count" (HTC) populations.
The data supplies two primary groups of information: 1) details on the mail return rates for each census tract in Cook County 2) Estimated demographic characteristics for each census tract in Cook County.
For detailed information on the data please go to the following link:
https://datacatalog.cookcountyil.gov/stories/s/hza3-k7kt