About the CHAS
The U.S. Department of Housing and Urban Development (HUD) periodically receives "custom tabulations" of Census data from the U.S. Census Bureau that are largely not available through standard Census products. These data, known as the"CHAS" data (Comprehensive Housing Affordability Strategy), demonstrate the extent of housing problems and housing needs, particularly for low income households. The CHAS data are used by local governments to plan how to spend HUD funds, and may also be used by HUD to distribute grant funds. For more background and general information on the CHAS data, click here: Background.
Access the Data
There are two ways to access the CHAS data. If you are comfortable working with large datasets, and you have appropriate software (ideally SAS, SPSS, or Stata, but Excel might suffice), you might download the raw data files. HUD is also working on an interactive online tool to tailor the CHAS data to your local market conditions and help guide your jurisdiction’s investments of housing and community development funding.
Raw data files
Custom Table Generator (under development)
2005-2007 CHAS Excel files

Data Documentation
The CHAS data are derived from Census data according to HUD’s specifications. For explanation of the raw data’s format, and a list of the variables used and their definitions, click here: Data Documentation.
Updates
HUD expects to post new CHAS tabs, for new years of ACS data, as they are obtained. The data and data documentation for these updated files will be clearly marked in the Data Access and Data Documentation pages. If any previously posted data or data documentation needs to be corrected or clarified, an explanation will be posted here, on the Update page.
Comments and suggestions should be sent to Paul.A.Joice@hud.gov with "CHAS feedback" as the subject line.