Sources
Every number on Groundwork comes from one of the datasets below, and each panel names the source it draws on.
Census Building Permits Survey
New privately-owned housing units authorized by building permits, by place. Survey-based with imputation; misses most ADUs and conversions. Loaded to cross-validate HCD APR permit counts, not as a panel source.
Updates monthly · Public domain; cite U.S. Census Bureau.
HCD Annual Progress Report
Jurisdiction-reported housing element progress: entitlements, building permits, and completions by income level, from annual reports due each April.
Updates annual · California open data. Self-reported by jurisdictions; HCD does not independently verify.
HCD RHNA Progress Report (6th cycle)
Each jurisdiction's 6th-cycle RHNA allocation by income band and cumulative building permits issued toward it. We derive prorated pace from these figures.
Updates annual · California open data. Progress is compiled from self-reported APRs and lags.
Zillow Home Value Index (ZHVI)
Smoothed, seasonally adjusted measure of the typical home value (35th-65th percentile band, all homes).
Updates monthly · Free with attribution on every page displaying the data; derivative charts allowed; no logos.
Zillow Observed Rent Index (ZORI)
Smoothed measure of the typical observed market-rate asking rent (repeat-rent index, mean of the 40th-60th percentile of listings, weighted to the full rental stock).
Updates monthly · Free with attribution on every page displaying the data; derivative charts allowed; no logos.
How we turn these into charts is on the methodology page.