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U.S. Census


The American Community Survey (ACS) is a nationwide survey conducted on an ongoing basis to collect data about the nation, states, counties, and places. The data are released in single-year, 5-year, and 3-year time periods.

The ACS estimates replaces information formerly gathered in the decennial census; data on the "Short form"/sample.

Time Periods

ACS estimates are time periods not a point in time.

Do: express data in time periods

“The child poverty rate for the 2005-2007 period was X percent.”

Do: compare data using same types of estimates

Do: compare estimates using data from the same survey years (periods)

Do: compare data from non-overlapping periods

Example: 2005-2007 ACS 3-year estimate and the 2008-2010 ACS 3-year estimate


Don't: refer to data as a year (use the time period)

Don't: compare estimates from overlapping periods

Example: don't compare 2005-2007 ACS 3-year estimates and 2006-2008 ACS 3-year estimates