U.S. Census: Introduction

• Data & Visualization Services Department
• U.S. Federal Government Publications
• Family History and Genealogy
• U.S. Economic Data
• GIS Data
• ArcGIS
• Data Visualization

When trying to obtain US census data, consider the following points:

• Level of aggregation: Do you need information on individuals or aggregated data?
• Geographic specificity: If aggregated, data for a single place, or comparison between different geographies?
• Geographic extent: If comparison, what units within what area? (e.g., all counties within a state, all census tracts within a county)
• Date(s) of interest: What time period are you studying?
• Date span: A single point in time, or track changes over time (time series)?
• Output needs: Do you need to see data on screen, download or print a pre-formatted table, or download data to analyze further?
• Periodicity of surveys: Understand that surveys may be decennial, annual, or represent a pool of observations over 3 or 5 years (e.g., American Community Survey).
• Changes in questions: Understand that different questions are asked as parts of different surveys, and the same basic question may vary somewhat over time.
  • The book Measuring America: The Decennial Censuses From 1790 to 2000 provides a nice overview of the questions asked during the first 22 censuses. PDF version / Paper version: Perkins/Bostock Library Reference Desk C 3.2: M46/2
  • Census Bureau's Through the Decades web pages (questions, instructions, etc., over time)
  • Questions and enumerator instructions for each census (from IPUMS-USA).
  • A quick-reference table summarizes population and housing questions from 1790 to 2000, compiled by Grace York at the University of Michigan.
  • The Census Bureau provides a chart that summarizes changes in race and ethnic categories over time.

Once you've thought through these issues, see the following tabs of this guide to find appropriate sources for your data.