Valuation and Assessment of Immovable Property (Almy, OECD)

Summary

Valuation and Assessment of Immovable Property (OECD Working Papers on Fiscal Federalism No. 19, 2014; paper dated 7 October 2013) by Richard Almy — a veteran assessment consultant and co-author of the IAAO's Fundamentals of Mass Appraisal — is the broadest international survey of how property is actually valued for tax. It "draws on published information and data on property tax policy and administration in 172 countries" and organises the field around three questions: "What is valued? How is it valued? And who values?"[1]

For the wiki it matters as the source behind two numbers Doucet cites second-hand — the per-property cost of a mass-appraisal system, and the typical accuracy of such systems — and as the authoritative statement that mass valuation is routine international practice, not a Georgist aspiration.

What It Establishes

• Cost per property (~EUR 20). In a discussion of when a high-quality valuation system is economically justified, Almy states: "The annual cost per property of operating such a high-quality system currently is about EUR 20 (based on experience in Canada, Netherlands, and United States)."[1] A footnote adds that "a comprehensive revaluation costs about $50 per property, which is about one-tenth of the cost of an appraisal of a house for mortgage purposes."[1]
• Cost as a share of revenue. "Total annual expenditures for property tax administration generally are in the range of 5 to 10 per cent of annual property tax revenues in developed countries," while valuation costs alone "can be as low as 1 to 2 per cent in high property tax countries like the United Kingdom and the United States."[1]
• Achievable accuracy (~10% error). The paper takes an "error rate" of 10% as representative because "discrepancies between estimated values and actual sales prices typically average about 10 per cent in high-quality mass valuation systems."[1]
• Mass valuation is standard and model-based. It documents that hedonic multiple-regression models have been used for immovable-property taxation since valuers in Scandinavia and North America developed them in the 1970s, and describes the specification–calibration–testing cycle and ratio studies that underpin modern CAMA — the practice the mass-appraisal-methods page describes.[1]

Relation to the Assessability Question

Almy supplies the cost leg of the assessability rebuttal. The land-cannot-be-assessed objection has two forms — "it can't be done accurately" and "it can't be done affordably." Kolbe et al. answer the first for land specifically; Almy answers the second for property assessment generally, with a per-property operating cost around EUR 20 and total administration at 5–10% of revenue in developed countries. Because a land value tax requires the land component that most systems already estimate, this is a ceiling on the incremental administrative burden, not an additional cost on top.

A precision correction to the retelling. Doucet's Does Georgism Work? summarises this as "~EUR 20 per property (≈1% of receipts)." The EUR 20 is verbatim correct. The "≈1%" conflates two different figures: Almy's ~1% is the valuation-only cost share in high-tax UK/US (the footnoted "1 to 2 per cent"), whereas total property-tax administration runs 5–10% of revenue. The EUR 20 is an absolute per-property figure and does not itself translate to a fixed revenue share — that depends on the tax rate and property values (Almy's Table 3 shows a high-quality system is "completely uneconomic" at effective rates around 0.01% and "easily justifiable only when effective tax rates reach at least 1 per cent").[1] For context, Doucet's Land Is a Big Deal (Ch. 24) sets these costs against 6–12% total collection cost for federal income tax and 3–13% for sales taxes — comparators from his book, not from Almy.

Limits

• General property assessment, not land-only. Almy's cost and accuracy figures cover valuing whole properties; they bound but do not isolate the cost of the land/building split that LVT specifically needs.
• Costs are "little studied." Almy himself cautions that "the costs and effectiveness of valuation systems seem little studied,"[1] so the EUR 20 rests on experience in three advanced administrations (Canada, Netherlands, US), not a systematic cross-country cost dataset.
• Working-paper caveat. It carries the standard OECD disclaimer that working papers "should not be reported as representing the official views of the OECD."[1]
• Rich-country figures. The affordability case is strongest where cadastral and sales-data infrastructure already exists; the paper is clear that low-tax and low-capacity systems must be "less ambitious."[1]

See Also

• Mass Appraisal Methods
• Objection: Land value can't be assessed accurately
• Doucet, Does Georgism Work?
• Kolbe et al., Land Value Appraisal Using Statistical Methods
• Hefferan & Boyd, Mass Appraisal Valuations in Australia
• IMF, Taxing Immovable Property

Sources

1. Richard Almy (2014), Valuation and Assessment of Immovable Property, OECD Working Papers on Fiscal Federalism No. 19, OECD Publishing, DOI 10.1787/5jz5pzvr28hk-en (paper dated 7 October 2013). Free official PDF: OECD; mirror: Lincoln Institute (the oecd-ilibrary docserver link returns 403; no Wayback snapshot exists). — used for: the ~EUR 20 per-property annual operating cost of a high-quality mass-valuation system; the $50 comprehensive-revaluation cost footnote; property-tax administration at 5–10% of revenue (valuation-only 1–2% in UK/US); the ~10% typical valuation error in high-quality systems; the 172-country survey scope; and the history of hedonic/MRA mass valuation. All figures verified verbatim against the PDF (2026-07-10).