All 50 states + DC · reviewed August 2026
Assessment & sales ratio studies
Every state measures how closely assessors' values track real sale prices. Those measurements are the statutory basis for level-of-assessment and uniformity appeals — and in 9 states the published ratio is applied directly to compute what your assessment should be.
Three numbers to know. The median ratio is the level a jurisdiction actually assesses at — frequently not the level its statute names. COD measures uniformity: the IAAO standard is 15 or less for residential, and a high COD means similar homes are assessed inconsistently, which is an equity argument even when the median looks fine. PRD outside 0.98–1.03 indicates lower-value homes are being over-assessed relative to higher-value ones.
A state's legal assessment ratio is a statutory multiplier and has nothing to do with the measured sales ratio. Confusing the two is the most common error in this subject — each entry below states which is which.
Alabama
Equalization Sales Ratio Study (Plan for Equalization, form ADV-1)
How you use it: ALDOR publishes the standards but not county ratio tables, so a level-of-assessment argument at the county Board of Equalization requires obtaining the county's own valuation-zone study by records request.
Legal standard: Property is appraised at fair market value then assessed at the class ratio — Class III (residential/agricultural) 10%, Class II 20%, Class I (utility) 30%. The ALDOR Plan for Equalization requires each county's ratio study to produce a median appraised-to-sale ratio of 98–102% per valuation zone with an overall COD of 20 or less.
No county ratio tables are published; the most recent Plan for Equalization found online is dated October 2022.
Alaska
Full Value Determination (in the annual Alaska Taxable report)
How you use it: The FVD funds schools rather than deciding appeals, but Alaska Taxable Table 2 publishes a weighted-mean assessed-to-value ratio and COD per municipality, which corroborates a non-uniformity claim to the local Board of Equalization under AS 29.45.190.
Legal standard: AS 29.45.110 requires assessment at full and true value (100% of open-market price). The Full Value Determination sets each school district's required local contribution; there is no statutory COD or median-ratio compliance band.
Arizona
Sales Ratio Study / Sales Ratio Summary
Median ratio
81.4%
COD (uniformity)
11.5
PRD
—
Study year
2016
How you use it: Cite a county median above the 82% residential target or a COD above the 15%/20% standard when appealing full cash value to the assessor and then the County or State Board of Equalization.
Legal standard: A.R.S. §42-11054(E) freezes the ratio guidelines as applied in 1993. Target median level: 82% for vacant land and residential, 81% commercial; compliance windows 74–90% and 73–89%. COD must be 15 or less in Maricopa and Pima, 20 or less elsewhere for residential. Entirely separate from the legal class ratio (Class 3 owner-occupied = 10% of full cash value).
ADOR does not post the summary publicly — county assessors receive it. The 2016 figures shown are the most recent publicly retrievable, not the most recent produced; request current data from ADOR or your county assessor.
Published: Annual (equalization cycle August–January)County-level figures: yesOfficial dataArizona appeal guide
Arkansas
Statewide Ratio Study (Ratio Study Summary Report)
How you use it: Use the county median and COD before the County Equalization Board to show the county assesses above the 20% statutory level, or that your parcel's own ratio materially exceeds the county median.
Legal standard: A.C.A. §26-26-304 sets the assessment level at 20% of appraised value, with the measured median required to fall between 18% and 22%. COD standards: counties under 50,000 parcels — residential 20 or less; 50,000+ parcels — residential 15 or less.
The per-county table is an attachment that did not render in automated extraction — open the PDF directly for county figures.
Published: Annual (covers counties in that reappraisal cycle)County-level figures: yesOfficial dataArkansas appeal guide
California
Assessment Practices Survey (NOT a sales-ratio study)
How you use it: California offers no ratio-based appeal — identical neighbours lawfully carry different assessments under Prop 13. An Assessment Appeals Board application must argue either that the factored base-year value was computed wrongly, or that current market value has fallen below it (a Prop 8 decline-in-value claim).
Legal standard: Proposition 13 makes taxable value the LESSER of the factored base-year value (acquisition value plus max 2%/yr) or current full cash value. Because assessed value is acquisition-based, there is no target market-value ratio for the roll and the BOE computes no median sales ratio, COD or PRD.
Colorado
Annual Property Assessment Study (the assessment audit)
How you use it: Cite your county's audit report — a residential median away from 1.00, a COD above 15.99, or a PRD outside 0.98–1.03 — when protesting actual value to the assessor and then the county Board of Equalization.
Legal standard: §39-1-104(16) C.R.S. mandates the study. State Board of Equalization standards: median sales ratio 0.95–1.05, COD 15.99 or less, PRD 0.98–1.03, PRB −0.05 to +0.05. Property is valued at actual value then multiplied by a statutory assessment rate that the legislature has changed repeatedly since 2020.
Published: Annual (report due September 15)County-level figures: yesOfficial dataColorado appeal guide
Connecticut
Equalized Net Grand List (from town-level sales-assessment ratio studies)
How you use it: Appeal to the town Board of Assessment Appeals (§12-111) arguing the assessment exceeds 70% of fair market value; the OPM town ratio corroborates that the town's roll as a whole sits above 70%.
Legal standard: C.G.S. §12-62a requires assessment at 70% of true and actual value; §12-62 requires revaluation at least every five years. OPM computes a sales-to-assessment ratio for each of the 169 municipalities in four classes. No COD or PRD is published and there is no statutory acceptable band.
Delaware
Assessment-to-Sales Ratio Study (Division III equalization)
How you use it: Used only to equalize school funding. Appeal to the county Board of Assessment Review on true value; the classic Delaware uniformity argument rests on the county's own assessment-to-sales ratio, not this study.
Legal standard: 9 Del. C. §8306 requires assessment at true value in money but Delaware sets no statewide percentage. Counties long used frozen base years, producing district ratios from 0.064 to 0.260, until court-ordered countywide reassessments took effect across 2024–2025 and reset ratios toward 100%. No COD or PRD standard exists.
Published: Annual (three-year smoothed average)County-level figures: noOfficial dataDelaware appeal guide
District of Columbia
Assessment Ratio Report
Median ratio
97.4%
COD (uniformity)
5
PRD
1.03
Study year
2024
How you use it: Appeal first to OTR then petition the Real Property Tax Appeals Commission, citing the report to show your own assessment-to-sale ratio exceeds the citywide or class median, or that class COD/PRD breaches IAAO standards.
Legal standard: D.C. Code §47-820 requires assessment at 100% of estimated market value and §47-823(c) requires this annual report. It benchmarks explicitly against IAAO standards (residential COD 15 or less, PRD 0.98–1.03).
Figures shown are FY2024 (overall median 97.4%, COD 5, PRD 1.03; residential 97.6%, COD 5, PRD 1.01). The FY2025 report is posted but its tables could not be extracted reliably — verify against the PDF.
Florida
Assessment Roll Evaluation — Overall Level of Assessment by Stratum
How you use it: Introduce DOR's certified county Level of Assessment at the Value Adjustment Board to argue just value should come down to the county's prevailing assessment level, alongside the §193.011 just-value criteria.
Legal standard: Fla. Stat. §193.011 requires assessment at just value, with the §193.011(8) costs-of-sale deduction applied in DOR studies. §195.096 requires DOR to compute the median and value-weighted mean per stratum at 95% confidence and publish results. No numeric acceptable band is set by statute, and neither COD nor PRD is a statutory requirement.
Published: Annual level computation; in-depth roll review at least bienniallyCounty-level figures: yesOfficial dataFlorida appeal guide
Georgia
Sales Ratio Study / State-Wide Equalized Adjusted Property Tax Digest
Median ratio
36.68%
COD (uniformity)
15.68
Above the IAAO standard of 15
PRD
1.0198
Study year
2023
How you use it: Georgia appeals expressly allow a 'uniformity of assessment' ground under O.C.G.A. §48-5-311 — cite the county's sales-ratio level and COD to show it assesses above 40% of fair market value or fails the residential COD standard.
Legal standard: O.C.G.A. §48-5-7 sets assessed value at 40% of fair market value. Digest approval standards: average assessment level per class must fall within 36–44%; COD must not exceed 15% residential and 20% other; PRD must fall within 0.95–1.10. Counties below 36% face additional state tax assessed against the governing authority.
The statewide figures shown are for digest year 2023, the most recent explicitly stated in DOR's annual report; later years appear only in trend charts.
Published: Annual (digest established by November 15)County-level figures: yesOfficial dataGeorgia appeal guide
Hawaii
How you use it: With no ratio study to cite, appeal to the county Board of Review and then the Tax Appeal Court on the county's own statutory grounds — typically assessment exceeding market value by more than a set percentage, plus lack of uniformity — proving both with your own comparable-sales analysis.
Legal standard: The Hawaii Constitution gives the counties exclusive authority over real property taxation. Each of the four counties requires assessment at 100% of fair market value under its own charter and code. No state agency conducts an equalization or ratio study and there is no COD or PRD regime.
Idaho
Idaho Counties' Ratio Study (EPB00660)
Median ratio
93.32%
COD (uniformity)
8.99
PRD
1.02
Study year
2024
How you use it: Cite the county study — an improved-residential median well below 100% or a COD above 15 — to the county Board of Equalization and then the Board of Tax Appeals to bring your assessment to the county's prevailing level.
Legal standard: Idaho Code §63-205 requires assessment at 100% of market value; Property Tax Rule 131 governs methodology. Compliance is tested with confidence intervals rather than a fixed band — a category failing the 90% confidence test is reported non-compliant and subject to Tax Commission equalization the following year.
Figures are the statewide Improved Residential category from the 2024 study (revised July 2025), not an all-property figure.
Illinois
Sales Ratio Study (Table 3, Illinois Property Tax Statistics); methodology in PTAX-1-E
How you use it: The county's IDOR median level of assessment is the denominator in an Illinois lack-of-uniformity claim: at the Board of Review or PTAB, show the assessed value exceeds proven market value multiplied by the county's three-year median level — which in Cook County means roughly 10–11% residential, not 33 1/3%.
Legal standard: 35 ILCS 200/9-145 requires non-farm property to be assessed at 33 1/3% of fair cash value; Cook County's classification ordinance sets roughly 10% residential. IDOR computes each county's median level of assessment annually and the equalization multiplier is 33.33% divided by the prior three-year average median. Illinois publishes no statewide median because the whole mechanism equalizes every county TO 33.33%.
Indiana
Ratio Study (part of the Annual Adjustment / trending process)
How you use it: Cite the county's DLGF-approved ratio study to the PTABOA or the Indiana Board of Tax Review to show your parcel is assessed above the township's prevailing level, or that dispersion shows non-uniform assessment.
Legal standard: Assessment standard is 100% of true tax value (market value-in-use); annual adjustments are required by IC 6-1.1-4-4.5. Counties must submit a ratio study to DLGF and receive an approval letter before values are certified. Mean, median, COD and PRD are reported per township and property class.
Iowa
Equalization study (built on assessment/sales ratio analysis)
How you use it: After an equalization order you may protest to the local board of review between October 9 and October 31, but only to remove the increase attributable to the order. Separately, the ratio evidence supports the Iowa Code 441.37 ground that an assessment is 'not equitable as compared with assessments of other like property'.
Legal standard: Iowa Code 441.21 requires assessment at 100% of actual value. Under Iowa Code 441.47–441.49 the Department orders an adjustment when a class's aggregate valuation is at least 5% above or below the Department's own determination.
The 2025 per-county order percentages are not published in one place on revenue.iowa.gov — county assessor sites republish them.
Published: Biennial — orders issued in odd-numbered yearsCounty-level figures: yesOfficial dataIowa appeal guide
Kansas
Kansas Real Estate Ratio Study
How you use it: Use the county residential median, COD and PRD at the informal or BOTA level to show the county appraises above 100% of market, or that dispersion and regressivity make your appraisal non-uniform.
Legal standard: Property is appraised at fair market value (K.S.A. 79-503a) then assessed at the classification rate — residential 11.5%, commercial 25%. K.S.A. 79-1486 mandates the study. Standards: acceptable median ratio 90.0–110.0%; the low end of the COD confidence interval must be 20.0 or less; PRD should fall between 0.98 and 1.03.
No statewide aggregate row exists. The 2025 study reports that 98.4% of statewide residential value met the level standard, but only 55.4% of commercial/industrial value did.
Kentucky
Assessment/Sales Ratio Study (KRS 133.250)
How you use it: KRS 133.250 requires each county to publish its percentage of fair cash value attainment — cite it to the local Board of Assessment Appeals or the Kentucky Board of Tax Appeals to show your assessment exceeds the level actually achieved county-wide.
Legal standard: Ky. Const. §172 requires assessment at 100% of fair cash value. The DOR manual sets the allowable range at 90–110%; PVAs of counties falling below 90% or exceeding 110% in a class must adjust. COD guidance: under 15% for single-family residences, under 10% in areas of new homes; above 20% indicates an equity problem.
Ratios are delivered to PVAs and published county by county rather than in a statewide table, so no single latest-year figure could be pinned.
Louisiana
Ratio studies are performed internally for parish review; no public statewide report located
How you use it: With no usable published statistics, appeal to the parish Board of Review and then the Louisiana Tax Commission on fair market value and the constitutional ratios directly.
Legal standard: La. Const. Art. VII §18 sets assessment percentages of fair market value — land 10%, residential improvements 10%, other improvements 15%, public service 25%. Parishes must reappraise at least every four years. The LTC annual report contains assessed-value tables by parish and class but no median ratio, COD or PRD.
Published: Not verifiable from primary sourcesCounty-level figures: noOfficial dataLouisiana appeal guide
Maine
State Valuation sales ratio study + Municipal Valuation Return Statistical Summary
How you use it: In an abatement request under 36 M.R.S. 841/843/844, apply the town's certified ratio to proven market value — if the certified ratio is 85%, an assessment above 85% of market value is excessive. This is the standard evidence a Maine Board of Assessment Review expects.
Legal standard: MRS certifies each municipality's equalized full value annually using real estate transfer tax declarations, trimming the highest and lowest observations. There is a two-year lag — the 2025 State Valuation reflects values as of April 1, 2023. Maine law imposes a minimum assessment ratio and a maximum quality (dispersion) rating on municipal assessing.
Maryland
Assessment Ratio Report
Median ratio
94.1%
COD (uniformity)
6.6
PRD
1.01
Study year
2025
How you use it: Cite Table IV for your county — median ratio, COD and PRD — before the Supervisor, the Property Tax Assessment Appeal Board or the Maryland Tax Court, to show you are assessed at a higher percentage of sale price than the jurisdiction's median.
Legal standard: Maryland assesses at 100% of full cash value; the report is required by Tax-Property Article §2-202(12). Reassessment runs on a three-year cycle with one third of properties revalued each year, so measured ratios lag the market.
Massachusetts
Statistical ratio analysis within BLA certification; Equalized Valuations (EQV) separately
How you use it: Massachusetts publishes no per-town median ratio or COD table, so an Appellate Tax Board overvaluation appeal is argued on comparable sales. The DLS certification standards are useful only as background that a community's values are stale.
Legal standard: M.G.L. c.59 §38 requires assessment at 100% of full and fair cash value. BLA certification includes a statistical ratio review and assessing units must be within 10% of full value, with COD limits. EQV under c.58 §10C is used for state aid, not individual appeals.
Published: Certification on a five-year cycle per community; EQV biennialCounty-level figures: noOfficial dataMassachusetts appeal guide
Michigan
County equalization studies / 24-month sales studies (Forms L-4021, L-4023, L-4024)
How you use it: At the March Board of Review or the Michigan Tax Tribunal, prove true cash value and show the assessed value exceeds 50% of it, using the county equalization department's class/neighbourhood sales-study ratio and ECF as corroboration.
Legal standard: The Michigan Constitution and the General Property Tax Act require assessment at 50% of true cash value. County equalization directors conduct sales studies and file recommended state equalized values each April. Michigan's studies are weighted-mean-based for equalization; the STC publishes no statewide median ratio, COD or PRD.
Minnesota
Sales Ratio Study
Median ratio
95.38%
COD (uniformity)
8.39
PRD
—
Study year
2025
How you use it: The DOR study is the standard exhibit in a Minnesota Tax Court petition under Minn. Stat. ch. 278 — show the county's residential median and argue your parcel's assessment-to-market ratio materially exceeds it, or that the COD shows non-uniform assessment.
Legal standard: Minn. Stat. 273.11 requires valuation at market value. The Department's stated acceptable target range for the median sales ratio is 90–105%; jurisdictions outside it are subject to State Board of Equalization orders.
Figures are the residential/seasonal statewide category. Minnesota publishes no PRD.
Mississippi
Appraisal/assessment ratio study under the DOR Standards of Acceptance (results not published)
How you use it: Mississippi publishes the standards but not the results, so object to the Board of Supervisors sitting as the Board of Equalization on true value plus the published Standards of Acceptance as the benchmark the county's roll must legally meet.
Legal standard: Miss. Code 27-35-50 requires assessment at true value; ratios by class are Class I (owner-occupied residential) 10%, Class II/III 15%, Class IV/V 30%. Standards of Acceptance: Class I acceptable range 85–115% with COD 20 or less; Class II/III 75–125% with COD 20 or less; COD above 25% is grounds for rejection; price-related bias index must fall between 0.92 and 1.08.
Missouri
Ratio Study (published as County Ratios by reassessment cycle)
How you use it: In a Missouri discrimination appeal before the State Tax Commission, compare your parcel's own ratio to the county's common level of assessment — but note the standard is high: the disparity must be grossly excessive, not merely a difference of opinion on value.
Legal standard: RSMo 137.115 sets statutory assessment percentages of true value — residential 19%, agricultural 12%, commercial 32%. The study measures each county's actual level against those, with ratios expected within about 10% of the statutory level. Missouri relies substantially on independent appraisals rather than sales alone.
Missouri publishes no COD or PRD, and the cycle dropdown had not posted 2025–2026 figures as of August 2026.
Published: Biennial (odd-year reassessment cycle)County-level figures: yesOfficial dataMissouri appeal guide
Montana
How you use it: There is no state ratio study to cite — appeal to the county AO and the Montana Tax Appeal Board purely on market value evidence, since sales data and any internal ratio analysis are confidential.
Legal standard: MCA 15-7-111 requires reappraisal to 100% market value every two years for residential and commercial property. There is no statutory acceptable-ratio corridor and no published equalization ratio. MCA 15-7-308 makes Realty Transfer Certificate sale prices confidential, and the administrative rule governing stratified sales-ratio procedures has been repealed.
Published: Biennial reappraisal; no public ratio studyCounty-level figures: noOfficial dataMontana appeal guide
Nebraska
Reports and Opinions of the Property Tax Administrator
How you use it: Nebraska's reports are genuinely dual-use: cite your county's published residential median, COD and PRD to the county board of equalization or TERC to argue your assessment sits above the county's level of value.
Legal standard: Neb. Rev. Stat. §77-201 requires residential and commercial property to be assessed at 100% of actual value and agricultural land at 75%. §77-5023 sets the acceptable equalization range TERC uses: 92–100% for residential and commercial, 69–75% for agricultural land.
Nevada
Report of Assessment Ratio Study
Median ratio
34%
COD (uniformity)
13.7
PRD
—
Study year
2026
How you use it: Show your county is outside the 32–36% statutory band, or that your parcel's ratio exceeds the county median, in an equalization claim to the County or State Board under NRS 361.356/361.357.
Legal standard: NRS 361.225 assesses property at 35% of taxable value. NRS 361.333(5)(c) requires the Department to flag possible under- or over-assessment when the median ratio of assessed to taxable value falls below 32% or exceeds 36%.
Nevada's study compares assessed value to independently determined TAXABLE value, not to sale prices, and covers only a rotating subset of counties each year — the figures shown are a study-sample statistic, not all 17 counties.
Published: Annual (rotating subset of counties)County-level figures: yesOfficial dataNevada appeal guide
New Hampshire
Equalization Reports / Assessment-to-Sales Ratio Study
How you use it: Divide your assessment by the property's true market value and compare to the town's DRA-certified median equalization ratio — if yours is higher, the assessment is disproportionate and the excess is abated under RSA 76:16, or on appeal to the BTLA or superior court.
Legal standard: RSA 75:1 requires assessment at full and true value; RSA 21-J:3 XIII requires annual equalization. The study uses arm's-length sales from October 1 to September 30, effective April 1, certified by May 1. DRA treats a COD of 20 or less and a PRD of 0.98–1.03 as acceptable.
The 2025 report set was inferred from DRA's statutory rhythm; the most recently URL-verified set is 2024.
Published: Annual (certified by May 1)County-level figures: yesOfficial dataNew Hampshire appeal guide
New Jersey
Table of Equalized Valuations (Director's Ratio) + annual Chapter 123 Common Level Range
How you use it: Prove true market value, divide your assessment by it, and compare to your district's Common Level Range. Above the Upper Limit, a reduction to true value × average ratio is MANDATORY. Inside the range, the assessment is affirmed even if it exceeds true value × average ratio. Below the Lower Limit the board must INCREASE your assessment — so appealing in an under-assessed district is affirmatively dangerous.
Legal standard: N.J.S.A. 54:4-23 requires assessment at true value, but each municipality assesses at its own percentage and the Director's Ratio measures it. Chapter 123 sets a Common Level Range of ±15% around the average ratio: Lower Limit = ratio × 0.85, Upper Limit = ratio × 1.15 (capped at 100%). Chapter 123 does NOT apply in a year the municipality implements a revaluation or district-wide reassessment.
Published: Annual (TEV certified October 1)County-level figures: yesOfficial dataNew Jersey appeal guide
New Mexico
Sales Ratio Study (conducted; no public report tables located)
How you use it: With no public tables, protest to the county Valuation Protests Board on market value and the 3% cap; a level-of-assessment argument requires a records request to the Property Tax Division.
Legal standard: NMSA 1978 §7-37-3 sets taxable value at 33 1/3% of the value determined for property taxation. §7-36-18 directs the department to conduct sales-ratio analyses. §7-36-21.2 caps annual residential valuation increases at 3%.
Published: Annual per statute; results not postedCounty-level figures: noOfficial dataNew Mexico appeal guide
New York
Residential Assessment Ratios (RAR), equalization rates, and the Market Value Survey equity report
Median ratio
—
COD (uniformity)
19.79
Above the IAAO standard of 15
PRD
—
Study year
2026
How you use it: Multiply proven full market value by the RAR to get the assessment that would be uniform, and claim the excess as an unequal assessment on the RP-524 grievance and then the SCAR petition — which expressly asks for the latest equalization rate or RAR. The RAR is usually stronger than the equalization rate for a house, because it is drawn from residential sales only.
Legal standard: RPTL 305(2) requires each assessing unit to assess at a uniform percentage of value, which it chooses itself — there is no statewide legal ratio. ORPTS measures it as the equalization rate (all property) and, for one-to-three-family homes, the Residential Assessment Ratio under RPTL 738. The RAR is the number used in individual challenges.
The 19.79 figure is the statewide MEDIAN of per-assessing-unit residential CODs from the 2025 Market Value Survey, not a COD computed over a single statewide pool. It is well above the IAAO standard of 15, which is itself usable in a uniformity case.
North Carolina
Sales Assessment Ratio Study (the Sales Ratio Book)
How you use it: Primarily a public-service-company equalization tool, but the county's published median ratio and COD are usable evidence that county-wide assessments have drifted from the statutory 100% standard, before the county Board of Equalization and Review or the Property Tax Commission.
Legal standard: G.S. 105-283/105-284 require assessment at 100% of true value as of the last general reappraisal; G.S. 105-286 requires octennial revaluation. The certified median's statutory function is to set the ratio applied to public service company property in a county's 4th and 7th years after revaluation.
Published: Annual (as of January 1)County-level figures: yesOfficial dataNorth Carolina appeal guide
North Dakota
Assessment Sales Ratio Study — Property Distribution Report
How you use it: Pull the median ratio, COD and PRD for your city or township to show your parcel is assessed above the local median or that uniformity is poor, supporting an abatement application under Ch. 57-23 or a protest to the local or county board.
Legal standard: N.D.C.C. §57-02-27: property is valued at true and full value, assessed value is 50% of that, and taxable value is 9% of assessed for residential. The State Board of Equalization increases valuations for any classification falling below a 90% median ratio, making the effective target band 90–100%.
Ohio
Sales-assessment ratio analysis (Residential Sales Data by County and Jurisdiction)
How you use it: File a DTE Form 1 complaint with the county Board of Revision arguing true value, citing the DOT jurisdiction median to show the auditor's values overshoot the 92–94% target; any reduction then flows through at 35%. HB 124 (effective March 2026) made the underlying sales sample a county-generated, appealable record — so it is now discoverable and contestable in a way it was not before.
Legal standard: R.C. 5713.01 requires appraisal at 100% of true value; taxable value is a uniform percentage capped by statute at 35% — the long-standing 35% assessment ratio, entirely separate from the measured sales ratio. R.C. 5715.24 requires the Tax Commissioner to determine annually whether each county is assessed as required by law. DOT targets median sales ratios of roughly 92–94% in a reappraisal or update year, against the IAAO 90–110% standard.
The published DOT dataset is stale — the file currently posted covers sales through 2018/2019. Current jurisdiction ratios come from the county auditor's own statistical study.
Published: Annual determination; sexennial reappraisal with triennial updateCounty-level figures: yesOfficial dataOhio appeal guide
Oklahoma
Equalization Study (annual assessment ratio study / performance audit)
How you use it: A county-compliance tool rather than a taxpayer remedy — protest to the County Board of Equalization on fair cash value and the 3%/5% caps, and request the OTC findings to argue your county's class ratios are out of band.
Legal standard: Okla. Const. art. X §8 assesses real property at 11–13.5% of fair cash value, locked per county; §8B caps annual increases at 5% (3% for homesteads). OAC 710:10-3-18 requires median audited assessment percentages by class, and a county complies only if within the 11–13.5% band AND all three real property classes fall within a 1.5-percentage-point deviation range.
No downloadable county ratio table is posted by the OTC; findings surface in State Board of Equalization minutes. County figures likely require an open-records request.
Published: Annual (reported to the State Board of Equalization in December)County-level figures: yesOfficial dataOklahoma appeal guide
Oregon
Assessor's Certified Ratio Study and Changed Property Ratio
How you use it: Because assessed value is capped by MAV, the ratio study rarely drives a homeowner appeal directly — petition the Property Value Appeals Board to lower RMV, which only cuts tax if RMV falls below MAV. The study and CPR are mainly useful for challenging trending factors or new-construction MAV.
Legal standard: ORS 308.232 requires real market value at 100% of RMV, and ORS 309.200 requires each assessor to prepare a certified ratio study and prove the target was achieved. But under Measure 50 assessed value is the LESSER of maximum assessed value and RMV.
Pennsylvania
Common Level Ratio (CLR) — annual STEB report with COD and PRD by county
How you use it: The most direct ratio-to-assessment conversion in the country: prove current market value and multiply by the county CLR in effect when the appeal was FILED to compute the correct assessed value. CLRs run on a July 1 – June 30 cycle — as of August 2026 the operative table is the 2025 CLR, effective July 1, 2026 to June 30, 2027. Note that PA publishes the CLR as a percentage while the Dept. of Revenue republishes its reciprocal as a realty-transfer-tax factor; use the STEB percentage for appeals.
Legal standard: 53 Pa.C.S. §8842(b)(1) requires STEB to establish a common level ratio of assessed to market value for each county. Counties assess at their own Established Predetermined Ratio, but under §§8844(e)(2) and 8854(a)(3) the board or court applies the CLR instead whenever it varies from the EPR by more than 15% — which in practice is nearly everywhere.
Published: Annual (certified by July 1)County-level figures: yesOfficial dataPennsylvania appeal guide
Rhode Island
Equalized Weighted Assessed Valuation (EWAV / AEWAV)
How you use it: Cite your town's published Ratio of Assessment to argue the assessment should be discounted to the same level — but because the figures run three years in arrears and carry no COD or PRD, a §44-5-26 appeal is fundamentally an overvaluation case.
Legal standard: R.I. Gen. Laws §44-5-12 requires assessment at full and fair cash value, with a statistical revaluation in the 3rd and 6th year and a full revaluation every 9 years. §16-7-21 directs the Division to determine each municipality's full value and Ratio of Assessment for the school-aid formula. No COD or PRD is published.
Published: Annual, reported three years after the assessment dateCounty-level figures: noOfficial dataRhode Island appeal guide
South Carolina
County Ratio Study (conducted but not published)
How you use it: With no published study, build the equivalent argument from the county's own assessment roll, or FOIA SCDOR for the county's findings. In practice South Carolina's 15% reassessment cap and the 4% owner-occupied ratio are the more productive levers.
Legal standard: S.C. Code §12-43-250 requires SCDOR to make sales ratio studies in all counties. Reg. 117-1720.2 sets the standards: a median appraisal level outside 80–105% of fair market value is unacceptable, as is an 'index of inequality' — ½(Q3 − Q1) ÷ median — above 15%. Legal assessment ratios are 4% owner-occupied and 6% other; reassessment is every 5 years with increases capped at 15%.
SC's index of inequality is quartile-based, so its 15% threshold is NOT directly comparable to an IAAO COD of 15.
Published: Annual; counties notified by June 1County-level figures: noOfficial dataSouth Carolina appeal guide
South Dakota
Sales Ratio Study (County Statistical Report and County Rankings)
How you use it: Use your county's published median and COD for your property class before the local, county and state boards of equalization — a live argument here, since many counties post CODs far above the IAAO standard of 15 (Aurora 37.3 and Beadle 25.3 in the 2025 study).
Legal standard: SDCL 10-11-60 requires the Secretary to publish the findings annually. Property is assessed at full and true value and taxable value is 85% of it. DOR applies a county equalization factor derived from the study. Median ratio, COD and PRD are reported by county and property class.
Tennessee
Appraisal Ratio Study Report
How you use it: The ratio's statutory job is equalizing centrally assessed utility property with locally assessed property. Where a county's published ratio is materially under 1.00 it still supports scaling your appraised value to the same measured level before the county board and the State Board of Equalization.
Legal standard: T.C.A. §§67-5-1604 to 1606 govern the study. Real property is appraised at 100% of value then assessed at a constitutional classification ratio — 25% residential and farm, 40% commercial and industrial. Counties reappraise on 4-, 5- or 6-year cycles.
Published: Annual reports; a study in every county at least every two yearsCounty-level figures: yesOfficial dataTennessee appeal guide
Texas
School District Property Value Study (PVS) and the separate Appraisal District Ratio Study
How you use it: Texas has the strongest ratio-type remedy in the country, but it does NOT run on the state's ratio study. Under Tax Code §41.43(b)(3) the ARB must decide in your favour unless the district shows your appraised value is at or below 'the median appraised value of a reasonable number of comparable properties appropriately adjusted' — a comparison of CAD APPRAISED VALUES of adjusted comparables, not sale prices. A Texas property can be at or below market value and still win an equal-and-uniform reduction. The PVS and MAP are district accountability tools and cannot change an individual account.
Legal standard: Tax Code §23.01 requires appraisal at 100% of market value. Gov't Code §403.302 requires the Comptroller to determine taxable value per school district. Tax Code §5.10 requires the Appraisal District Ratio Study measuring the median level of appraisal and uniformity per CAD and category. Separately and independently, Tax Code §41.43(b)(3) and §42.26 create the 'equal and uniform' remedy.
Only a school district, or an owner whose tax liability on the studied property is $100,000 or more, has standing to protest PVS findings.
Published: PVS annual (each district at least biennially); ratio study annual; MAP review every two yearsCounty-level figures: yesOfficial dataTexas appeal guide
Utah
Assessment/Sales Ratio Study
How you use it: Cite the published county-and-class median ratio, COD and PRD to the county Board of Equalization under §59-2-1004, either to show the county's overall level is below 100% (so your value should scale down) or that dispersion exceeds the R884-24P-27 standard.
Legal standard: Utah Code §59-2-103 requires assessment at 100% of fair market value, with a 45% exemption for primary residential property. Rule R884-24P-27 sets performance standards: level of assessment 95–105% for urban residential and 90–110% for other classes; COD thresholds vary by county size and class; PRD above 1.03 indicates regressivity, below 0.98 progressivity.
Vermont
Equalization Study (Common Level of Appraisal and Coefficient of Dispersion)
Median ratio
70.33%
COD (uniformity)
—
PRD
—
Study year
2025
How you use it: The most consequential ratio study in the country for homeowners: 32 V.S.A. §4467 gives the Board of Civil Authority and the state appraiser explicit statutory authority to apply the CLA to reduce a listed value once fair market value is established. Grieve to the listers, then the BCA.
Legal standard: 32 V.S.A. §3481 requires listed value to equal fair market value; §5405 requires a CLA and COD for each municipality. §4041a triggers a mandatory reappraisal when a municipality's COD exceeds 20 or its CLA falls below 85% or above 115%, with education and transportation funds withheld for non-compliance.
The 70.33% figure is the statewide CLA — an aggregate grand-list-to-equalized-value ratio, not a median of individual sales ratios. In the 2025 study 130 of 255 municipalities exceeded the §4041a COD-20 reappraisal trigger. Note also that Act 183 of 2024 changed how the CLA is applied to education tax from July 1, 2025.
Published: Annual (certified to towns by January 1)County-level figures: noOfficial dataVermont appeal guide
Virginia
The Virginia Assessment/Sales Ratio Study
Median ratio
75.17%
COD (uniformity)
—
PRD
—
Study year
2024
How you use it: Cite your locality's median ratio and COD from Table 1 to the local Board of Equalization (§58.1-3378) or circuit court (§58.1-3984) — a locality median well below 100% supports scaling your assessment to the measured level.
Legal standard: The Virginia Constitution and Va. Code §58.1-3201 require real estate to be assessed at 100% of fair market value; §58.1-207 mandates the annual study. Unlike Utah or Vermont it carries NO reassessment trigger — TAX cannot order a locality to reassess based on it.
The 75.17% statewide median is from the 2024 study (down from 83.25% in 2023), drawn from 95,219 sales. Virginia publishes no statewide COD or PRD summary.
Washington
Ratio Study — 'Measuring Real Property Appraisal Performance'
Median ratio
94%
COD (uniformity)
8.4
PRD
—
Study year
2025
How you use it: Important caveat: DOR's Boards of Equalization manual states that boards 'cannot consider the appraised values of comparable properties when establishing the market value of the subject'. So carry the clear-cogent-and-convincing burden with actual comparable SALES, and use the ratio study only as context on whether the assessor's roll is systematically high.
Legal standard: RCW 84.40.030 requires assessment at 100% of true and fair value. RCW 84.48.075 requires DOR to determine and certify each county's ratio annually and permits adjustment where market-value standards are not met. RCW 84.41.030 requires revaluation with physical inspection at least every six years.
2025 statewide residential COD 8.4%, nonresidential 17.3%. 32 of 39 counties met the IAAO residential COD range; 7 counties had PRDs outside 0.98–1.03. No statewide PRD is published.
West Virginia
West Virginia Assessment Ratio Study
How you use it: Cite the county-and-class median ratio and COD to the county commission sitting as the Board of Equalization and Review (§11-3-24) to argue the appraised value exceeds the county's measured level, or that the county falls outside the 90–110 band.
Legal standard: W. Va. Code §11-3-1(d) requires assessors to value property at 60% of true and actual value. The study compares the assessor's APPRAISED value (the 100% figure) to sale price, and an aggregate or median ratio between 90 and 110 is considered acceptable.
A statewide summary table exists in the report (Table II.J) but its cells could not be extracted automatically — open the PDF for statewide figures.
Wisconsin
Equalized Values with per-municipality assessment ratios (Summary of Aggregate Ratios)
How you use it: Your municipality's assessment ratio is printed on every Wisconsin tax bill — use it to convert assessed value to implied full value. If a 79% ratio implies a full value of $367,600 and your home is worth less, that supports both a §70.47 Board of Review objection and a later §74.37 excessive-assessment claim or §70.85 DOR revaluation request.
Legal standard: Wis. Stat. §70.32 requires assessment at full value and §70.57 requires DOR to certify equalized value by August 15. §70.05(5)(b) requires each municipality to assess all major classes within 10% of full value at least once in any five-year period; non-compliance escalates to a DOR-ordered supervised assessment at municipal expense in the sixth year.
DOR publishes no statewide assessment ratio and no COD or PRD by municipality. By 2022, 42.5% of Wisconsin municipalities had ratios below 80%.
Published: Annual (certified by August 15)County-level figures: yesOfficial dataWisconsin appeal guide
Wyoming
No published statewide study; county assessors run internal statistical analysis reviewed by the State Board
How you use it: With nothing published, request the county assessor's own sales-ratio study and CAMA statistical output for your Land Economic Area in discovery, then argue to the County Board of Equalization that the measured median, COD or PRD violates the SBOE Ch. 5 §6 standards.
Legal standard: Wyo. Stat. §39-13-103(b)(ii) requires valuation at fair market value, with residential assessed at 9.5%. SBOE Rules Ch. 5 §6 sets the equalization thresholds: level of appraisal 0.95–1.05; COD 15 or less for improved residential and 20 or less for improved commercial and vacant land; PRD 0.98–1.03.
Published: Annual internal review; no public reportCounty-level figures: noOfficial dataWyoming appeal guide
Where a figure is shown as "—" the state either publishes only county-level tables or publishes nothing usable. That is recorded honestly rather than filled with an estimate — follow the official data link for your county's numbers.
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Compiled from state revenue departments, tax commissions, equalization boards and statutes. Figures change annually — confirm against the official source before relying on them in a filing. This is not legal advice.