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2009 Data Release

posted July 20, 2011

Release of DataFerrett with new features to access 2005-2009 ACS 5-Year Summary File

Following a successful 3 week test in the Beta version of DataFerrett, the U.S. Census Bureau released an updated version of DataFerrett into production. DataFerrett is a free online tool that can analyze and extract data from many sources, including the ACS Summary File. The updated version of DataFerrett now offers a new mapping feature, corrections to some known bugs and access to the following additional summary levels from the 2005-2009 ACS 5-year Summary File.

  • American Indian Area/Alaska Native Area/Hawaiian Home Land
  • Metropolitan Statistical Area/Micropolitan Statistical Area-State
  • Combined Statistical Area
  • Combined Statistical Area-State
  • New England City and Town Area
  • Congressional Districts-111th-County
  • State-State Legislative District (Upper Chamber)
  • State-State Legislative District (Lower Chamber)

New and Notable
2007-2009 ACS 3-year estimates

posted January 11, 2011

ACS 3-year estimates released January 11

  • ACS estimates are based on data collected from January 1, 2007 to December 31, 2009.
  • Estimates are available for geographic areas with populations of 20,000 or more.
  • ACS 3-year estimates are NOT Census 2010 data.

New tables available

New and Notable
2005-2009 ACS 5-year estimates

posted December 14, 2010

First-ever ACS 5-year estimates released December 14

  • ACS 5-year estimates are NOT Census 2010 data.
  • ACS estimates are based on data collected from January 1, 2005 to December 31, 2009.
  • Estimates are available for every state, county, city, town, place, American Indian Area, Alaska Native Area, and Hawaiian Home Land, as well as for census tracts and block groups.

Browse our additional New and Notable items below or get detailed information on where to find the different data products.

2005-2009 ACS 5-year maps

The Census Bureau has released new county-level maps based on the 2005-2009 ACS 5-year estimates. All of the topics also have Census 2000 maps and data to determine statistical significance.

Select geographies unavailable on American FactFinder

The ACS staff determined that we are unable to release a small number of 2005-2009 ACS 5-year geographies that were scheduled for AFF release in January 2011. All subject tables will not be published on AFF for two summary levels:

  • "Principal City" within "Metropolitan Statistical Area/Micropolitan Statistical Area
  • "Principal City" within "New England City and Town Area"

The missing geographies are available on the FTP site in comma-separated values (CSV).

Block group data available only in the Summary File

Detailed American Community Survey tables for block groups will only be included in the Summary File product; they will not be published in American FactFinder. Visit the Summary File page for more information.

Tables available only in the Summary File or as CSV files

  • 295 Detailed Tables not published on American FactFinder are available as csv files on the FTP site (down to the Census tract level) and in the Summary File (down to the block group level).
  • Subject tables are not available on American FactFinder for two Summary levels: "Principal City" within "Metropolitan Statistical Area/Micropolitan Statistical Area" and "Principal City" within "New England City and Town Area." These tables are available on the FTP site in comma-separated values (CSV).

Vintage of geographic boundaries

The 2005-2009 ACS 5-year estimates for legal areas are based on boundaries as of January 1, 2009 as reported to the Census Bureau by local stakeholders through the Boundary and Annexation Survey (BAS). Statistical area boundaries published in the 2005-2009 ACS 5-year estimates are defined using Census 2000 definitions. Visit our Geography page to learn more.

posted December 8, 2010

Data products availability

The 2005-2009 ACS 5-year data products

will include

  • detailed tables
  • data profiles
  • narrative profiles
  • subject tables
  • geographic comparison tables
  • and thematic maps

will not include

  • comparison profiles
  • state ranking tables
  • selected population profiles

Get detailed information on where to find the different data products.

Subject availability

The 2005-2009 ACS 5-year estimates include estimates on most (but not all) topics included in the survey. Several topics that were added or modified in 2008 and 2009 are not included in these 5-year estimates. These include Bachelor's field of degree, disability, marital history, health insurance coverage, and service-connected disability status and ratings. The first 5-year estimates for these topics will be available in the 2013 release of the 2008-2012 5-year estimates (except for Bachelor's field of degree, which will be available in the 2014 release of the 2009-2013 estimates). For a complete list of topics covered on the ACS questionnaire, browse Subjects included in the American Community Survey.

Tools & Tips for Comparing ACS 5-year Data to Census 2000 Data

Use our quick guide to check for high-level comparability between ACS and Census 2000 estimates

Use our Table Comparison Tool to search by specific table numbers

Browse by ACS subjects for comparable data to Census 2000 subject data

New and Notable
2009 1-year estimates

posted September 28, 2010

ACS Briefs

For the release of the 2009 ACS 1-year estimates, the Census Bureau produced reports for the American Community Survey Briefs series -- short reports on specific topics based on the newly released data.

New weighting methodology for data products

As a result of concerns raised about the ACS estimates of total and subgroup population in some incorporated places, the ACS has adopted subcounty total population controls. This change in methodology will affect the ACS estimate of the total number of people in a particular location, but the distribution of characteristics for the most part remains comparable across years. This change applies to the 2009 ACS 1-year estimates and all future ACS 1-year, 3-year, and 5-year estimates.

The basic method is to add a procedure that controls for total population at the subcounty level while controlling for total population and additional demographic characteristics at the county level. The controls for both the subcounty and county level come from the Population Estimates Program (PEP) which is released annually by the Census Bureau. Subcounty estimates used to construct weights in the multiyear ACS products rely on an average of PEP’s subcounty estimates over the 3- or 5-year period. In general, one should expect very close agreement between the ACS estimates and the PEP estimates, but they may not be exactly equal. As with any methodological change, a small number of places may observe changes in the distribution of characteristics that are the result of the new methods. To learn more about possible impacts on characteristics, see the Research Note  [PDF 28KB] on this new method.

Revised data from the 2008 ACS

Due to the discovery of several errors, corrected 2008 data appear in the 2009 ACS 1-year Comparison Profiles and the ACS briefs. Corrected 2008 data will also be used to produce the 2005-2009 ACS 5-year and 2007-2009 ACS 3-year data products as well as future multiyear products. We do not plan to rerelease any of the existing 1-year or 3-year ACS tables that include 2008 data on American FactFinder, or any of the ACS PUMS files that include 2008 data. For more information, please refer to the errata notes.

Metro areas

The 2009 ACS 1-year release will be the first 1-year ACS release to include all metropolitan statistical areas. In order to provide complete metro area coverage the Census Bureau decided to publish 1-year data for the Carson City, Nevada and Lewiston, Idaho-Washington Metropolitan Statistical Areas even though they do not yet meet the 65,000 population threshold.

Imputation rates

Data users may also notice that the imputation rates for most ACS variables are lower in 2009 than in 2008. Two factors account for this change. In 2009 the ACS program resumed full Failed Edit Follow-Up (FEFU) operations after a partial suspension in 2008. In FEFU, households who have returned a mail form but whose data failed a completeness check are called to collect the missing data. This operation is designed to improve the final quality of mail-returned questionnaires. In addition, we introduced a computer-assisted instrument for group quarter person interviews in 2009 that resulted in more complete group quarter data collection.

New tables for the 2009 ACS 1-year release

  • There will be 13 new detailed educational attainment tables presenting data from the new question on bachelor’s field of degree, only published in the 2009 ACS 1-year data products.
  • Health insurance coverage will include new race iterated tables B27001A-I and C27001A-I: Health Insurance Coverage Status by Age (By Race and Hispanic Origin).

See details on new and modified tables in Product Changes


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Source: U.S. Census Bureau | American Community Survey Office | Email ACS | Last Revised: September 20, 2012
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