Skip to Main Content

U.S. Census and Demographic Information

General guide to understanding and finding demographic data produced by the U.S. Census Bureau

Introduction to Census Geography

Understanding Census geography is not always as simple as it would seem. there are traditional methods for dividing up geography in the United States that most people are familiar with, such as states, counties, and zip codes. The Census uses its own methods and terminology for geography as well, the most prominent of which is a division known as a "Census tract," which divides up counties. The links on this page are provided to help users comprehend Census geography and how it can be used to better understand population and demographic data.

The following image offers a basic outline of Census geographic divisions. For a full explanation of the diagram, see the Hierarchy Diagrams page on the Census Bureau website

Examples of Tracts, Block Groups and Census Blocks

Census Tracts in Ann Arbor, Michigan

Block Groups in Ann Arbor, Michigan

Census Blocks in Ann Arbor, Michigan

What's my census tract or block group number?

Online Resources

Print Resources

Various maps and publications by the Geography Division of the U.S. Census Bureau are available in the Hatcher Graduate Map Library, as well as other libraries on campus, and electronically. Most of these publications are from the second half of the 20th century through the early 21st century. See Library Catalog Search for a full listing.

The books below are all print guides for Census geography available through the University library system.