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CHICLA 330: Gentrification In Latinx Comm. (Spring 2022) : Census geography

Information about and links to library resources helpful for CHICLA 330: Gentrification in Latinx Communities. Emphasis on retrieving Census data.

Getting Census data for neighborhoods

The Census does NOT provide data for "neighborhoods." How cities define neighborhoods varies between cities and and other municipalities.. Some municipalities (such as Chicago) don't have official boundaries for neighborhoods.

Instead, you will have to determine which Census tracts and Census block groups make up a neighborhood. (See descriptions in box below.)  

The boundaries of a group of Census tracts and the boundaries of a neighborhood most likely won't align perfectly, and it's okay.  This is an issue that's known and accepted among researchers, city planners, and other professionals.

When looking at maps of Census tracts and block groups in Social Explorer, as you mouse over a tract or block group, a box should appear with the number of the tract/block group. I recommend noting the tract and block group numbers for your neighborhood for future reference.

Three important geographic terms

Descriptions based on entries in the Census glossary.

"Place" is roughly equivalent to "city," "village," etc, in the Census.

  • In Social Explorer, look for “Census place.”
  • Other data retrieval sites may use just “place.”

"Census tracts"

  • Small, relatively permanent statistical subdivisions of a county.
  • Their primary purpose: to provide a stable set of geographic units for the presentation of decennial census data.
  • Generally have between 1,500 and 8,000 people, with an optimum size of 4,000 people. 

"Block group" (or "Census block group")

  • Statistical divisions of census tracts and composed of clusters of census blocks.
  • A census block group consists of all census blocks whose numbers begin with the same digit in a given census tract.
  • Typically contain between 600 and 3,000 people, with an optimum size of 1,500.
  • Smallest type of geographical unit for which the ACS 5-year estimates have data.

Main Geographic Divisions & Hierarchies

The following diagram outlines the divisions of census geography, from the nation as a whole to the census block.

This diagram is useful if


Why This Matters

When retrieving Census data, you'll be asked what geographic level you want the data from, whether for the whole U.S., or for Census tracts.

Not all data are available for every kind of geography.

Data becomes available for different geographic levels at different times.

Geographic Definitions & Concepts

More detailed information about census geography can be found at the following sites: