Insee-Notaries Indices Certified Label (ASP)

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In 2011, the Authority of Public Statistics (ASP) initiated a labeling process of public statistics, originating from the use of administrative sources; produced outside the official statistical service (Insee and ministerial statistical services).



Before 1997, INSEE only published a price index for old apartments in Paris. But in 1997, the Superior Council of Notaries (CSN) wanted to create a price index for housing which was located outside Paris. Each trimester, the notaries collect the data in order to calculate each index according to the relevant market.

The Insee-Notaires de France indexes for old housing prices provide a measure for changing the price of second-hand dwelling at a constant quality on the housing market in France. The price used for the development of the index is the net seller selling price, excluding transfer duties, notary fees and agency fees.

The Insee-Notaires de France index on provincial housing prices was established by Convention No. 1998 00067 through the calculation and publication of price indices for housing sold in provincial towns.

Regarding old housing in Paris, reference should be made to convention n°2000 000 94 of May 16, 2000. It sets the conditions for INSEE's participation in the calculation, validation and publication of the index for the price of old apartments, sold free by mutual agreement on the Parisian market (Paris and the departments of Ile-de-France).

Why label the Insee-Notary index?

This labeling aims to guarantee a methodological framework to the users of these statistics, in keeping with the European Statistics Code of Practice, in the same way as the statistics produced by the public statistical service.

After an in-depth examination of the production and diffusion processes, ASP decided to label the Notary-Insee quarterly indices on March 28, 2018, calculated from the Perval real estate database, fed by the Notaries of the provinces:

  • for apartments and houses: Hauts-de-France region (with Nord-Pas-de-Calais detail), Auvergne-Rhône-Alpes region (with Rhône-Alpes detail) and Provence-Alpes-Côte d'Azur region; the entire Province; Metropolitan France, entire France (excluding Mayotte);
  • for apartments: city of Lyon and city of Marseille, cities of more than 10 000 inhabitants (distinguishable city centers and suburbs), other agglomerations and rural.
  • for houses: city of Lille

The indexes on Ile-de-France calculated from the commodity base, labeled since 2011.

  • for each of the Ile-de-France departments: all, houses and apartments (except houses for Paris);
  • for inner suburb groupings, the Outer suburbs and the entire region, but also the region outside Paris.

Notaries Indices certified Label-Insee Price : calculating method and diffusion

The Notaries-Insee price indices for old housing provide a method of price developments at a constant quality on the housing market, which an average (or median) price cannot entail. It goes through changes in terms of the structure of the real estate market. The method to calculate the Notaries-Insee index has been defined by INSEE and the Notary. These price indices are based on a statistical method, known as "hedonic".

This method is based on econometric models, breaking down house sales prices depending on their features. Through the use of these models, coefficients measuring the impact of each physical feature is estimated within each of the strata, which means, each real estate market (territories within which real estate price developments are considered to be homogeneous). Through the use of these coefficients, the prices of tracked properties are estimated each quarter. Price changes by stratum, are then aggregated for the calculation of departmental and regional indices.

The methodological principles of the indices are presented in detail in "The Notary-Insee price indices for old housing", Insee Methods No. 132. The methodological notes below sum up the method:

The second-hand housing price index makes it possible to measure the evolution of selling prices and to enrich statistical information on the housing market in France. The Notaries-Insee indexes relate to old houses and apartments.

In order to be considered as an old property, it must be:

  • the first sale if it takes place more than 5 years after the date of the works’ completion
  • the second sale

Atypical properties (rooms, lofts, workshops, castles) or acquisitions made by real estate professionals are excluded from the calculations of every index.

  • Indexes of older property (french version) 
  • Indexes of Notaries-INSEE (methodological note in french version)

Where are these price indexes displayed?

In order to guarantee equal access for all and under the same conditions, to inform on Notary-Insee indices, as required by the European Statistics Code of Practice, Notaries and Insee broadcast information through various mediums:

Notarial real estate databases

Notaries are required to estimate the value of real estate, whether for family law (inheritance, donations, sharing, etc.), real estate law (negotiations, etc.) and asset management (IFI declaration, wealth management advise...). In this context, in order to have elements to compare the valuation of real estate, they have been feeding a data file of real estate transactions, since 1994. The acts of sale of real estate directly come from the notary offices located throughout the national territory. Properties located in the provinces (including French overseas department, excluding Mayotte) are registered in the "Perval database", and those located in Ile-de-France in the "BIEN database".

The national file now contains more than 17 million mutations, and all types of property are registered in the latter (apartments, houses, lands, buildings, business premises, garages, agricultural property, viticulture property). The law dated March 28, 2011 to modernize the judicial or legal professions and certain regulated professions formalized this database, by establishing a new public service mission for notaries, which "contribute to the dissemination of information related to transfers of properties, for consideration.