American Community Survey

The American Community Survey from the U.S. Census Bureau is considered the replacement for the census “long form.”  Instead of collecting data every 10 years on education, occupation and other socio-economic characteristics, the ACS happens every year with resulting 1-year, 3-year and 5-year estimates for geographies that meet certain population thresholds.

Get the Data

• Access all of the data via American FactFinder. 
• Interactive maps from the New York Times for select variables nationwide

Find out when to use 1-year vs. 3-year or 5-year estimates. For those who want more detail on the methods used to collect the data and insights on margins of error, use of small area data and other topics, your best bet is the ACS website. 

Margins of Error and Statistical Significance

• Online ACS Calculator: This tool can test for significance or compute a value from 2 existing values (e.g., a percentage of total)
• ACS Statistics Calculator: This spreadsheet makes it easier to calculate margins of error and statistical significance from ACS estimates.
• The Search for Significance: A Crash Course in Statistical Significance: A brief tutorial about margins of error and statistical significance and how they relate to the ACS (InContext: Nov-Dec 2008).

Comparing to Census 2000

The 5-year estimates (and the other years from ACS) are not always comparable to the long-form data from previous censuses. Here are tools to help find comparable tables between the ACS and Census 2000.

• Web Comparison Tool
• Handbooks
• Presentations
• E-Tutorial  (1 hour)

Fast Facts on the ACS Estimates

1-Year Estimates

The 2011 ACS 1-year estimates are based on data collected between January 2011 and December 2011.

• Published for selected geographic areas with populations of 65,000 or greater
• Represent the average characteristics over calendar year
• Have smaller sample size than the 3-year and 5-year estimates
• Are more current than the 3-year estimates and 5-year

3-Year Estimates

The 2009-2011 ACS 3-year estimates are based on data collected between January 2009 and December 2011.

• Published for selected geographic areas with populations of 20,000 or greater
• Represent the average characteristics over the 3-year period of time
• Have larger sample size than the 1-year estimates but smaller than the 5-year

5-Year Estimates

The 2007-2011 ACS 5-year estimates are based on data collected between January 2007 and December 2011.

• Published for small geographic areas
• Represent the average characteristics over the 5-year period of time
• Have larger sample size than the 1-year and 3-year estimates
• Are less current than the 1-year and 3-year estimates

Related Links

• ACS release schedule
• ACS products
• ACS documentation, user notes and errata notices
• Uexplore (Missouri Census Data Center)