Coefficient of variation is calculated by dividing the standard deviation by the mean or average ratio and multiplying by 100. Fourteen counties meet this standard. Acceptable coefficients of dispersion depend on property type but should typically be 20% or less. 6, pp. The variance is The Kansas Constitution requires that all taxable Please review the necessary reporting forms and step-by-step instructions of the reappraisal process. Nineteen counties have coefficients of dispersion for residential properties greater than 15 percent. The Kansas Constitution requires that all taxable The Illinois Even with that reversal, property tax uniformity has tended to improve over the last 32 years. Fundamental to the administration of the property tax is the concept that all property should be appraised and assessed on a uniform basis. improvement in property tax assessment uniformity until that trend was reversed by the bursting of the real estate bubble in 2008. Equity - Is measured by the coefficient of dispersion (COD). Coefficient of Dispersion The standard measure of assessment uniformity is Coefficient of Dispersion, or COD. Under Berrios, the average coefficient of dispersion for first-pass valuations of commercial and industrial properties during the study period was 98, nearly five times the standard of 20. The COD should be 0=< on improved residential property and 0=<20% on all other classes. Coefficient of Dispersion - The relative dispersion or variability of assessments from the median. Washington Department of Revenue Property Tax Division Annual Valuation Team (360) 534-1362 10/02/12 4 The coefficient of dispersion (COD) is the most used measure of uniformity in ratio studies, and the only other one we will be discussing today. Counties with 50,000 or less inhabitants: Three year average of the median level of assessment – not more than 35.33% and not less than 31.33% of fair cash value of property within the assessment jurisdiction. (See Property Tax Statistics, Sales Ratio and Equalization Tables.) Fundamental to the administration of the property tax is the concept that all property should be appraised and assessed on a uniform basis. 144-148. What Is a Reappraisal? The IAAO Standard suggests that residential properties have a coefficient of dispersion less than 15 percent. The two main reasons why Appraisal districts need to consistently assess all property at 100% of market value. that result by the number of ratios. Property Tax Fiduciary 1.11. 1-12. Gastwirth (1982), "Statistical properties as a measure of tax assessment uniformity", Journal of Statistical Planning Inference, Vol. A coefficient of dispersion (COD) not greater than 15.00%. 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