The American Community Survey (ACS) is an ongoing, nationwide, monthly survey covering approximately three-million households each year and is now the source for all of the socioeconomic data that was formerly obtained from the decennial census. ACS data is available for three types of releases depending on population size: annually, three-year periods and five-year periods.

Annual ACS data are available for all geographies (e.g., U.S., states, counties, municipalities, places) with a population of 65,000 or more.

Three-year period ACS estimates are available for all geographies with a population of 20,000 or more.

Five-year period ACS estimates are available for all geographies down to census tracts and block groups.


Data and Reports


Cautions, Documentation and Guidelines on Using ACS Data

ACS Annual Data : 2010 || 2009 || 2008 || 2007 || 2006 || 2005 || 2004 || 2003 || 2002

ACS Three-year Data : 2008 to 2010 || 2007 to 2009 || 2006 to 2008 || 2005 to 2007

Socioeconomic Characteristics for Maryland's Jurisdictions and Places :
Census Transportation Planning Products (CTPP) : 2006 to 2008


2006 to 2008 County to County Commutation data (ACS)

ACS Five-year Data : 2006 to 2010 || 2005 to 2009

ACS 2006-2010 Selected Characteristics for Inside/Outside Priority Funding Areas (PFAs)


Map Application :
2006-2010 American Community Survey with Coefficient of Variation

Calculations of Statistical Significance & MOEs of Combinations of ACS Data


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

Note: Calculations include "Significance test for Difference between two Estimates", "Calculate the Standard Error of the Difference or Sum of Two Estimates", "Calculate the Standard Error of Sum of More Than Two Estimates", "Calculate the Standard Error of a Proportion" and "Calculate the Standard Error of a Ratio"