House price data at street level

THE GOVERNMENT has announced plans to improve the reliability of house price data in France, with public access to statistics on a street-by-street basis.

CNIS, France’s national statistics body, has produced a report recommending that the figures currently published by a host of different sources be standardised and brought together to improve their credibility.

Under the current system, the national property body Fnaim, the notaires network and half a dozen private estate agency chains all publish figures – often within a few days of each and freqently with contradictory findings.

For example, in the first quarter of 2010, house prices nationwide were up 7% according to Century21, down 2% according to Fnaim and down 4% according to the notaires.

CNIS praised the wealth of data that was available on the housing market from different sources, but said not enough was being done to collate, analyse and present it in a credible way.

The report was commissioned by Housing Minister Benoist Apparu, who said: “We do not currently have good enough statistical tools to give us a reliable view of the property market.

“Our ambition is to be able to provide data at street level.”

The reason for the big differences in the statistics is because they all compiled differently, using different sample sizes.

The notaires figures are based on the number of actes de vente signed each quarter. Fnaim’s data comes from a sample of 10% of the group’s members and is based on the compromis de vente, not the final sale document.

SeLoger.com publishes data from 17,000 agents. MeilleursAgents.com uses a sample of 300 estate agencies, and Century21 and Laforêt produce their own figures based on their 900 agencies around the country.