Freddie Mac engaged ESI, in collaboration with the Wharton GIS Lab and the Penn Institute for Urban Research, to develop the National Land Use Restrictiveness Index. The Index creates a standardized measure of zoning-permitted housing density at the U.S. Census Block Group level across the country to provide researchers and policymakers with a consistent, nationally comparable dataset to measure the relationship between land use regulations and housing affordability.
ESI compiled zoning regulations from approximately 1,000 municipalities and counties and integrated protected lands data from the USGS Protected Areas Database. This dataset covers roughly 40 percent of the U.S. population and 50 percent of U.S. land area across 32 states, with strong representation of large urban municipalities where housing demand is greatest. For areas without direct zoning data, ESI developed a model using observed zoning data for each state and more than 90 variables from national datasets measuring spatial characteristics, land cover, and road network features to generate statistically grounded predictions of restrictiveness. The index was constructed entirely from free, publicly available data to ensure reproducibility.
Initial research using the index confirmed that zoning is more restrictive in higher-income areas and less restrictive in lower-income areas, providing empirical grounding for the widely held view that land use regulations contribute to decreased housing affordability in the nation’s most desirable markets. The index has been made available to researchers as a standardized resource for analyzing the role of zoning in housing markets.
ESI produced the publicly available National Land Use Restrictiveness Index, a Census Block Group-level dataset covering approximately 40 percent of the U.S. population, along with underlying methodology documentation for use by researchers and policymakers.
