An Examination of Sales Ratio Data and Sources Incorporated into the 50-State Property Tax Comparison Study

The 50-State Property Tax Comparison Study, jointly produced by the Minnesota Center for Fiscal Excellence (MCFE) and the Lincoln Institute of Land Policy, uses sales ratios to more accurately reflect how assessment error affects property tax bills across the nation. In practice, sales ratios are used in a variety of other ways by state and local governments. Although the standards of the IAAO (International Association of Assessing Officers) are likely present in all sales ratio studies, the publicly available data varies from raw data and in-depth reports on its uses, to single indicators that lack full description of the actual metric used. In a very few cases, it is unclear whether actual ratio studies are performed. In the context of the 50-State Property Tax Comparison Study, we find that sales ratios produced across the U.S. at the state and local level vary significantly in specificity by property type and purpose.