The American Community Survey


The American Community Survey (ACS) is a new approach to producing critical information about the characteristics of local communities. It eliminated the need for a long form in the 2010 Census and is a key part of the Census Bureau's Decennial Census Program. The ACS publishes social, housing, and economic characteristics for demographic groups covering a broad spectrum of geographic areas in the United States and Puerto Rico. Every year the ACS can support the release of single-year estimates for geographic areas with populations of 65,000 or more. The ACS also accumulate sample over 3-year and 5-year intervals to produce estimates for smaller geographic areas including census tracts and block groups.

Census bureau has released single year ACS since 2006 summer for areas with populations greater than 65,000. Began in December 2008, the Census Bureau has released 3-year averages estimates for areas with populations greater than 20,000. Started in 2010, five-year averages estimates have been released for all geographic areas, regardless of population size.

American Community Survey Home Page at the Census Bureau is the official site. ACS data can be accessed via the Census Bureau's American FactFinder web application.

Washington State Office of Financial Management also set up an ACS resources website. It provides basic instructions, important links, and selected ACS data for Washington State.

CSSCR provides Washington State ACS data files in SAS, STATA and SPSS format and related materials on our website. Each data collection will be provided in its own group as they become available. Beginning in 2009, ACS data collection has been mainly focused on 5-year ACS estimates. National data and other states can be acquired by request; please contact the data archivist at txtian@u.washington.edu.

To access the ACS data in different year estimates, please click the buttons on the right.

Calculations of Statistical Significance and MOEs of Combinations of ACS Data

NY SDC developed spreadsheets with examples for determining statistical significance and calculating the MOE and SE for summing/subtracting, proportion and ratios.

Spreadsheet to Calculate If Two Estimates is Statistically Significant

Spreadsheet for Calculating Margins of Error and Statistical Significance for Sums, Proportions and Ratios

University of South Florida also provides an ACS Statistical Analyzer dealing with the precision of ACS estimates. This Excel-based analyzer and its report are available through the USF website.