How Property Value Data Is Collected and Updated

Property value data in Uncovero reports is drawn from official sources: municipal assessment rolls, land registries, or government house price indices, depending on the country and city. This guide explains the general mechanics behind these figures.

Sources vary by country

In the UK, property price data typically comes from HM Land Registry (England and Wales) or the equivalent registry body, recording actual completed sale prices. In Canada and the US, figures are more often drawn from municipal assessment rolls, which record assessed value for tax purposes rather than sale price directly.

Update frequency

Sale price registries are usually updated as transactions complete and are officially recorded, which can involve a lag of weeks to months after the actual sale. Assessment rolls are typically updated on a fixed annual or multi-year cycle set by the local authority, regardless of when individual sales occur.

Median vs average

Where a report shows a median value, this represents the middle value in a sorted list of sales or assessments, not a mathematical average. A median is generally more resistant to distortion from a small number of unusually high or low sales, which is why it is commonly preferred for area-level reporting.

Why a figure can lag the current market

• Registry recording delays between sale completion and public record
• Assessment cycles that do not align with calendar years or market conditions
• Low sales volume in smaller areas, which can mean a reported median is based on relatively few transactions

For a current, specific valuation of an individual property, a professional appraisal or a real estate agent's comparative market analysis will be more accurate than any historical dataset.