Library Contact
Clark Library
Hatcher Graduate Library 2 South
Census Workshop Slides
Looking for Census Data? Start here
- data.census.govCensus Bureau's freely available data portal. It contains data for the most recent 2 decennial censuses as well as the American Community Survey.
To search by address and identify tract numbers use the Census Geocoder
- Social Explorer This link opens in a new windowSubscription database available to University of Michigan affiliates. Provides easy access to demographic information about the United States, from 1790 to present, to create maps and reports.
Census Bureau APIs and FTP
- Census Data Resources for DevelopersAPIs for 2000, 2010 and 2020 decennial data as well as support forums
- Census Bureau FTP ServerFor bulk access to census data files
Background Information on Census Topics
- Encyclopedia of the U.S. Census: from the Constitution to the American Community SurveyProvides a resource to the history, politics, content, procedures, and uses of the decennial census of the American population, including the fallout from the 2000 census and recent issues affecting the administration of the 2010 count
- Census GlossaryDefinitions of terms used in Census data
Introduction to Census Data
The Decennial Census:
The decennial census is a constitutionally mandated count of the population of the U.S. which is conducted by the government every ten years. The count is used for apportioning Congressional seats, as well as many other purposes, such as demographic research, allocating funding, and informing public policy.
Historical Changes:
The Census has changed greatly over time. Though the first Census in 1790 did little more than count population, over the years it has grown to include many other types of information. Many questions and terminology (e.g. racial categories) have changed over time as well.
The Long Form and the American Community Survey:
Over time Congress became concerned that there were too many questions. In 1940 the Long Form was created as a way of finding out more detailed information (e.g. questions on income and educational attainment) from a sample of the population. The long form of the Census was sent to 1 in 6 households. The 2000 Census was the last time the long form was used. Since 2000, the American Community Survey has replaced the long form. The American Community Survey is an ongoing survey of a sample population that will provide us with detailed and more current information.