Data sources

Active launch sources

• U.S. Census Bureau — ACS table B25103 (median real estate taxes paid)
  Median real estate taxes paid (baseline effective-rate numerator). Refresh: annual. Attribution: U.S. Census Bureau, American Community Survey (ACS) 5-year, table B25103.
• U.S. Census Bureau — ACS table B25077 (median home value)
  Median home value (baseline effective-rate denominator). Refresh: annual. Attribution: U.S. Census Bureau, American Community Survey (ACS) 5-year, table B25077.
• NAIC — Homeowners Insurance Report
  Average homeowners premium by state & policy form (HO-3). Refresh: annual. Attribution: National Association of Insurance Commissioners (NAIC), Homeowners Insurance Report.
• FEMA National Risk Index (OpenFEMA)
  Natural-hazard risk (flood, wildfire, etc.), expected annual loss. Refresh: on_release. Attribution: FEMA National Risk Index.
• California State Board of Equalization — Proposition 13
  California base-year value, change-of-ownership reassessment, and annual inflation cap. Refresh: varies. Attribution: California State Board of Equalization, Proposition 13.
• Florida Department of Revenue — Save Our Homes assessment limitation
  Florida change-of-ownership reassessment and homestead assessment-growth limitation. Refresh: varies. Attribution: Florida Department of Revenue, Save Our Homes assessment limitation.
• California State Board of Equalization — Homeowners' Exemption
  California owner-occupied principal-residence exemption amount, eligibility, and filing deadline. Refresh: varies. Attribution: California State Board of Equalization, Homeowners' Exemption.
• Florida Department of Revenue — Homestead Exemption
  Florida homestead exemption amount, tax treatment, eligibility guidance, and application. Refresh: varies. Attribution: Florida Department of Revenue, Homestead Exemption.

Freshness and limitations

Government datasets are often historical. ACS and NAIC figures can lag current market conditions, while FEMA risk is a relative county indicator rather than an insurance price. Pages therefore show an as-of date and confidence level, and insurance uses a deliberately wide budgeting range.