New Use of HUD Income Limits and ACS Data in PA Study Could Be Replicated in Other States

A new study from the Community Affairs Department of the Federal Reserve Bank of Philadelphia (FRBP) utilizes innovative methods to analyze housing affordability based on American Community Survey (ACS) data, and concludes that even in the relatively “cool” housing markets of Pennsylvania, conditions deteriorated dramatically for the lowest income renters during the housing boom.

The number of affordable housing units available to renters with extremely low incomes (ELI) in the state decreased from 49 units per 100 ELI renter households in the 2000 census to 43 units per 100 ELI renter households in the middle of the decade, the study found. Additionally, the study notes that the proportion of the lowest income families paying more than 30% of their income for housing, those who are considered to have an unaffordable housing cost burden, increased significantly after 2000.

In performing the study, the authors of the FRBP study combined data from 2005 and 2006 American Community Survey (ACS) and compared the resulting data to the 2000 Comprehensive Housing Affordability Strategy (CHAS) data from HUD. The CHAS data are a special tabulation of housing affordability data and combine data from the “long form” of the 2000 Census that asked a large sample of Americans a detailed set of questions, including about rent and income, with HUD Section 8 income limits. The ACS is meant to replace the long form in 2010 by asking a smaller sample of households a similar set of questions every year beginning in 2005.

The sample size of the ACS in any single year is significantly smaller than the old Census long form, which limits its reliability analyzing smaller areas. However, combining the data from multiple years can increase the sample size. Because the ACS is a new tool, researchers are still exploring how to achieve the best results using the publicly available data.

The FRBP analysis uses a few novel approaches to create a dataset highly comparable to the 2000 CHAS data, including combining data from just two years and linking the data to HUD’s published income limits for metro areas and counties. The report includes comprehensive appendices so that others may use the same methodology in their states.

The study provides a county-to-county and region-to-region analysis within Pennsylvania using both datasets, and compares Pennsylvania to other states such as New York, West Virginia and Ohio using the 2000 data.

The report, Affordability and Availability of Rental Housing in Pennsylvania, by Erin Mierzwa, Kathryn P. Nelson, and Harriet Newberger, and associated tables and appendices are available at: http://www.philadelphiafed.org/community-development/publications/special-reports/rental-housing/index.cfm