National Statistical Institute of France

The Directorate of Demography and Social Statistics (DSDS) produces social statistics such as the consumer price index, the population census and the majority of household surveys such as the Labour Force Survey, the Cost of Labour Survey and the Housing Survey.

88 avenue Verdier - CS 70058 - 92541 Montrouge Cedex FRANCE

The harmonised index of consumer prices (HICP) is a consumer price index (CPI) that is calculated according to a harmonised approach. It measures the change over time of the prices of consumer goods and services acquired by households (inflation).

Due to the common methodology, the HICPs of the countries and European aggregates can be directly compared.

European classification of individual consumption according to purpose (ECOICOP)

The HICP covers the final monetary consumption expenditure of the household sector.

The main statistical variables are price indices.

The basic unit of statistical observation are prices for consumer products.

3.6.1. Statistical target population

The target statistical universe is the 'household final monetary consumption expenditure' (HFMCE) on the economic territory of the country by both resident and non-resident households. The household sector to which the definition refers, includes all individuals or groups of individuals irrespective of, in particular, the type of area in which they live, their position in the income distribution and their nationality or residence status. These definitions follow the national accounts concepts in the European System of Accounts.

3.6.2. Coverage error population

Not available.

3.7.1. Geographical coverage

The HICP refers to the economic territory of a country as referred to in paragraph 2.05 of Annex A to ESA 2010, with the exception that the extraterritorial enclaves situated within the boundaries of a Member State or a country are included and the territorial enclaves situated in the rest of the world are excluded.

3.7.2. Coverage error regions

For the price collections performed in the field, the price observations are carried out in a random sample of urban units that are representative of urban units with more than 2,000 inhabitants throughout the country. As of January 2023, the island of Mayotte has been integrated in the field of both the CPI and HICP. This territory is now treated the same way as the others.

Concerning scanner data that have been used to calculate the consumer price index for supermarkets and hypermarkets in metropolitan France for industrial food, maintenance and personal and home care products since January 2020, all the data are selected regardless the size of the urban unit.

3.8.1. Start of time series

The HICP series started in January 1997.

3.8.2. Start of time series - national specifics

See the HICP database

The French HICP started in January 1996.

2015=100

The following units are used:

• Index point
• Percentage change on the same period of the previous year (rates);
• Percentage change on the previous period (rates);
• Percentage share of the total (weights).

HICP is a monthly statistics.

Harmonised Indices of Consumer Prices (HICPs) are harmonised inflation figures required under the Treaty on the Functioning of the European Union. Regulation (EU) 2016/792 of the European Parliament and the Council of 11 May 2016 (OJ L 135) sets the legal basis for establishing a harmonised methodology for the compilation of the HICP and the HICP-CT.

This regulation is implemented by Commission Regulation (EU) 2020/1148 of 31 July 2020.

Further documentation, can be found in Eurostat’s website - HICP dedicated section, namely recommendations on specific topics, under the methodology page, and guidelines, under the quality page.

Not available.

Regulation (EC) No 223/2009 of the European Parliament and of the Council, of 11 March 2009, on the transmission of data subject to statistical confidentiality to the Statistical Office of the European Communities.

Treatment of confidential data

Statistical surveys are those that have received the approval set out in article 2 of the Law no. 51-711 of 7 June 1951 on Obligation, Coordination and Secrecy in Statistical Matters and which are included in the list of official statistical surveys published in the Journal Officiel each year.

The only rule imposed by statistical secrecy is the impossibility of direct or indirect identification. In practice, statistical secrecy is considered to be upheld if the knowledge of a characteristic relating to an individual cannot lead to the knowledge of another characteristic with which it is cross-referenced in a table.

The files are rendered totally anonymous insofar as they do not allow for the identification of the retail outlets, the urban units in which the price collections are carried out or the details of the consumption segments included in the calculation of the price index. The published aggregated data do not allow for this identification. The data made available to researchers on an occasional basis are completely anonymised.

The list of the retail outlets in which the prices are surveyed are secret and are not transmitted outside INSEE, or even within INSEE, other than to the units responsible for calculating the price index.

In line with the Community legal framework and the European Statistics Code of Practice Eurostat disseminates European statistics on Eurostat's website (see point 10 - 'Accessibility and clarity') respecting professional independence and in an objective, professional and transparent manner in which all users are treated equitably. The detailed arrangements are governed by the Protocol on impartial access to Eurostat data for users.

The HICP is released according to Eurostat’s Release calendar.

The calendar is publically available and published at the end of the year for the full following year.

The national calendar is available on the Insee website https://www.insee.fr.

Insee's publication calendars: https://www.insee.fr/en/information/2107811?debut=0

Eurostat's calendar: https://ec.europa.eu/eurostat/news/release-calendar

Each month, according to the planned schedule, the HICP and the national CPI are disseminated via https://www.insee.fr website in the form of a publication in the Informations rapides collection; this publication is also translated into English. The publication is embargoed until the official publication time, which is set at 8.45 a.m., as for the main economic indicators. Only journalists of the AFP (Agence France Presse) receive the embargoed information by email 30 minutes before the official publication time, i.e. at 8.15 a.m.

After the embargo has been lifted, all series of the index can be found in the Macro-economic Database on the INSEE website.

The CPI and HICP indices are disseminated up to level 4 of ECOICOP (5-digit code). The additional level (361 items), encoded to 6 digits, is specific to the annual publication of French consumer price indices. In addition, several indices for special groups of products used for short-term economic analysis, which are included in the Informations rapides, are also available in the macro-economic database.

Monthly

After the embargo has been lifted, all series of the index can be found in the Macro-economic Database on the INSEE website. The CPI and HICP indices are disseminated up to level 4 of ECOICOP (5-digit code). The additional level (361 items), encoded to 6 digits, is specific to the annual publication of French consumer price indices. In addition, several indices for special groups of products used for short-term economic analysis, which are included in the Informations rapides, are also available in the macro-economic database.

The data available in the macro-economic database are published at a sufficiently detailed level to allow users to search for indicators that will be useful for their analysis.

In addition to Eurostat dissemination, a national publication schedule is disseminated to journalists at the end of each month (on the 25^th) by the INSEE Press Office and published online (on the 31^st) at www.insee.fr

In addition to Eurostat dissemination, national publication takes place in the 'Informations Rapides' on the CPI which give the main results with comments. 'Informations Rapides' on the CPI and HICP can be printed out.

In addition to Eurostat dissemination, the results at a more detailed level are stored in a national database, called the macro economic database.

Some microdata may be available to allowed researchers through a secure data access center: www.casd.eu.

Not available.

The HICP Methodological Manual provides the reference methodology for the production of HICP. (https://ec.europa.eu/eurostat/web/products-manuals-and-guidelines/-/KS-GQ-17-015)

10.6.1. Documentation on methodology - national specifics

The general and methodological documentation can be found on the Insee.fr website.

All of the available documentation can be downloaded. This documentation is drafted in French and some documents have been translated into English.

See Eurostat's Compliance Monitoring Reports for France on the web page: Quality - Harmonised Indices of Consumer Prices (HICP) - Eurostat (europa.eu).

At the level of French official statistics, the CPI is submitted to the Official Statistics Quality Label Committee. This committee consists of a President, a rapporteur and three commissions empowered to issue a recommendation on the application submitted. The members of the commissions are designated by order (Order of 2/05/2013) in the Journal Officiel because they represent civil society or INSEE.

In each of these commissions, experts are appointed by the president of the committee at the rapporteur's proposal. Their role is to analyse the procedure used to create the index (in particular, the method, sampling and sample design, the collection protocol, quality controls, etc.) and the adaptation of the publication to the stated objectives.

After examining the application (Commission of 17 April 2019), the Official Statistics Quality Label Committee attributed the label of public interest and statistical quality to the price index production procedure, with binding force for the years 2020 to 2024.

11.1.1. Quality management - Compliance Monitoring

Compliance Monitoring

11.1.2. Quality assurance - national specifics

Quality control is implemented at all stages of the production process.

During the collection, the price differences are monitored automatically by the IT applications on the collectors' tablet computers. Collectors can correct or validate the values.

The managers of Price Sites validate the collectors' prices before the transfer to a national application: in particular, they monitor the product replacements and all prices outside the price range.

Sectoral Managers at the Price Division also possess tools to check the price recordings when the indices for which they are responsible change in an unusual manner.

The IT programs do not perform calculations if the data are incomplete.

The Manager of the Production Section monitors the conformity of data for the calculation of the HICP and CPI aggregates.

The production of the Price Index is standardised using dedicated IT applications.

11.2.1. Compliance monitoring - last report and main results

The last available compliance or follow-up reports can be found Eurostat’s web page: Quality - Harmonised Indices of Consumer Prices (HICP) - Eurostat (europa.eu)

11.2.2. Quality assessment - national specifics

European control: INSEE responds to requests submitted by Eurostat on a regular basis.

The conformity of the HICP to the HICP legislation and other European recommendations was last assessed by Eurostat in 2013, and followed up in 2018.

Control by the Quality Label Committee: at the level of French official statistics, the CPI is submitted to the Official Statistics Quality Label Committee. This committee consists of a President, a rapporteur and three commissions empowered to issue a recommendation on the application submitted.

Their role is to analyse the procedure used to create the index (in particular, the method, sampling and sample design, the collection protocol, quality controls, etc.) and the adaptation of the publication to the stated objectives.

After examining the application (Commission of 17 April 2019), the Official Statistics Quality Label Committee attributed the label of public interest and statistical quality to the price index production procedure, with binding force for five years.

In addition to being a general measure of inflation, the HICP is also used in the areas of:

• wages, social benefit and contract indexation;
• economic forecasting and analysis;
• measuring specific price trends;
• accounting purposes and deflating other series;
• inflation targeting by central banks;
• cross-country economic comparisons.

The euro area (evolving composition) index is used by the European Central Bank (ECB) as the main indicator for monetary policy management. The ECB and the European Commission's Directorate-General for Economic and Financial Affairs (DG ECFIN) use the HICP for assessing price stability and price convergence required for entry into European Monetary Union.

Other users include: National Central Banks, financial institutions, economic analysts, the media and the public at large.

12.1.1. User Needs - national specifics

CPI and HICP data are used for national, European and international (IMF, OECD) purposes. National and European institutions (Government, Bank of France, European Central Bank) use them for analysis in the short and long term as well as for economic and political decision-making. CPI are often used in order to chain-link different contracts and minimum wages.

Since 2018, a committee of users of CPI has have a meeting on a year basis. It consists of researchers, economists, institutions, representatives of the society.

Not available.

All ECOICOP indices at 5-digit level are produced.

The scope of the HICP is household final monetary consumption expenditure that occurs, throughout the whole of France (including Mayotte since 2023).

The national weights of the ECOICOP items are determined according to the data derived from the National Accounts.

For items representing a very low level of consumption (below 1/1000 of the consumption of the HICP), no prices are recorded. Only the sub-categories 12.6.2.2 (financial consulting and brokering), 10.5.0.0 (education not definable by level) and 04.1.2.1 (rentals actually paid for secondary residences) are not monitored.

The sample is updated annually to take account of changes in consumption behaviours and, in particular, to introduce new goods or services. The revisions concern the list and the content of varieties in addition to the breakdown according to forms of sale and per urban unit.

All ECOICOP/HICP sub-indices whose weights represent for more than one thousandth of the total expenditure covered by the HICP (except for the sub-categories mentioned above) are transmitted to Eurostat on a monthly basis.

The HICP is calculated every month on the basis of approximately 1,600 consumption segments.

See : https://www.insee.fr/fr/statistiques/2022137 Échantillonnage des agglomérations de l’IPC pour la base 2015

Not available.

The full set of HICPs is published each month according to Eurostat’s Release calendar, usually between 15 and 18 days after the end of the reference month.

Each year, the January release is published at the end of February to allow for the annual update of the weights, both of individual product groups and the relative country weights of Members States in the country group aggregates.

The euro area flash estimate is published on the last working day of the reference month or shortly after that.

Since the March 1997, launch of the HICP release, the HICP for the country groups aggregates has always been published on the dates announced in Eurostat’s Release calendar.

HICPs across Member States aim to be comparable. Any differences at all levels of detail should only reflect differences in price changes or expenditure patterns.

To this end, concepts and methods have been harmonised by means of legislation. HICPs that deviate from these concepts and methods are deemed comparable if they result in an index that is estimated to differ systematically by less than or equal to 0.1 percentage points on average over one year against the previous year (Article 4 of Council and Parliament Regulation (EU) 2016/792).

HICP data are fully comparable over time. There have been several improvements in methodology since HICP was introduced with the aim of improving reliability and comparability of the HICP. These changes may have introduced breaks in time series. However back calculations under the newer standards were performed when appropriate basic data was available.

The CPI and HICP classification is consistent with the 5-digit ECOICOP classification. Around the 15^th of each month m+1, to coincide with the publication of the definitive CPI and HICP, other complementary indicators are published: overall index corrected for seasonal variations, index excluding public tariffs and products with volatile prices corrected for tax measures (core inflation), and index for the large retail sector. Indices which are representative of the different household categories are also published (at a monthly or annual rate according to the household category). All of these indices are consistent with the HICP.

The HICPs are internally coherent. Higher level aggregations are derived from detailed indices according to well-defined procedures.

Not available

The HICP series, including back data, is revisable under the terms set in Articles 17-20 of Commission Implementing Regulation (EU) 2020/1148.

17.1.1. Data revision - policy - national specifics

The publication of the Consumer Price Index (CPI) is carried out twice for a given month. A provisional estimate is published at the end of the month and the definitive index is published on or around the 15^th of the following month. The definitive CPI, used for indexing many public and private contracts, cannot be revised.

The HICP can be revised within the limits defined by Articles 17-20 of Commission Implementing Regulation (EU) 2020/1148.

In 2016, a modification of the harmonised index of consumer prices from January to May was carried out in order to correct an error concerning fresh products.

18.1.1. Weights

The weights of the Consumer Price Index (CPI) and the Harmonised Consumer Price Index (HICP) are updated each year. They are used to aggregate the 21,000 indices calculated by family of elementary products and geographic area of collection. These weights represent the share of expenditure associated with the index concerned with regard to household consumption covered by the CPI/HICP.

18.1.1.1. Compilation at elementary aggregate level

The HICP brings together approximately 30,000 elementary indices. An elementary index generally represents the cross-referencing of one consumption segment and one urban unit ('var-agglo').

First-level or elementary-level indices are calculated using non-weighted aggregation formulas because there is insufficient data to weight the elementary observations within each pairing (consumption segments x urban units). Two formulas are used according to the type of consumption segment:

• if the consumption segment consists of highly comparable products in terms of their quality, the Dutot formula will be applied;
• if the consumption segment consists of excessively heterogeneous products, the Jevons formula will be applied.

18.1.1.2. Compilation of sub-index weights

To aggregate the detailed indices at the consumption segment level and calculate an overall index, the CPI uses a set of weights; this is based on National Accounting data when possible, i.e. when the National Accounting data provide the required level of detail. In compliance with the Eurostat regulations, the weights adopted for a year y are the National Accounting data for the semi-definitive account for the year Y-2 aged by the change in prices measured by the CPI in Y-1 and by the volume indices when available.

In addition, when the national accounts do not provide sufficiently detailed information, other sources are used. This applies to the price indices for the French Overseas Departments (DOM) in particular, which now use data from the most recent Household Budget Survey (2017/2018). More generally, for the most detailed levels of the price index, levels below those of the 5-digit ECOICOP, in which neither the National Accounts nor the Household Budget Survey provide an estimate of the relative share of the different consumption items, new sources such as scanner data are used.

The compilation of sources allows for the creation of a transitional table for the change from the National Accounting product classification to the ECOICOP classification.

For a given year, territory (whole of France and DOM) and ECOICOP item, for all of the household consumption items linked to this ECOICOP item, we add together the product of the amount of a consumption item derived from the National Accounts with the coefficient derived from the transitional table, a price correction coefficient and a volume correction coefficient.

The matrix used for the transition from products to functions was determined independently of the choice of sample. In this way, the amounts of almost all items can be calculated using the semi-definitive accounts for Y-2 and the matrix. The non-weighted items resulting from this calculation are due to coefficients that were deemed to be negligible when the matrix was created.

As for 2021 and 2022, in 2023, instead of using volume indices 'when available' we applied volume indices between Y-2 and Y-1 for all the sub-indexes.

These volume indices are based on Quarterly Accounts data for the whole 2022 year (respectively for the whole 2020 and 2021). They are available at a 100-level breakdown. Transition tables between the semi-definitive account, these volume indices in the Quarterly Accounts 100-level nomenclature and our ECOICOP makes it possible to derive volume indices for each of our 6-digit ECOICOP items.

Turnover indices are also used for a few items for which we want to refine the volume indices provided by Quarterly Accounts, for example to apply different volume indices to hairdressing (ECOICOP 12111 and 12112) and funeral services (12703) which are mixed together in the 100-level breakdown of the Quarterly Accounts while it is not satisfactory to apply the same volume indices.

18.1.1.3. Compilation of sub-index weights

The reference period up to and including the item level (5-digit ECOICOP) is the year Y-2 (National Accounts). Below this level, the reference period depends on the source. However, the priority is given to the most recent sources. The weights are reviewed annually.

18.1.1.4. Weights – plausibility checking

The sub-categories 12.6.2.2 (financial consulting and brokering), 10.5.0.0 (education not definable by level) and 04.1.2.1 (rentals actually paid for secondary residences) are not monitored. Access to price data for the first two sub-categories is problematical and feasibility studies regarding the production of an index are in progress. For the last sub-category, the monitoring of this rental category would require a significant extension of the sample currently used by the housing survey. In so doing, only one index for all rentals is produced and classified in function 04.1.1.

18.1.1.5. Price updating

The price correction is automatically applied to all items, using the Consumer Price Index: change in the indices between the average for Y-2 and December of Y-1. In this way, we take account of major changes in the value of items whose prices have clearly fallen or risen.

A volume correction is also applied, but only to items for which there is a known significant variation in volume, according to miscellaneous sources. These corrections concern information processing equipment, in particular. They are determined on the basis of the most recent data available from professionals (GfK, Gartner). For 2021, 2022 and 2023, instead of using volume indices 'when available' we will applied volume indices between Y-2 and Y-1 for all the sub-indexes.

The correction is applied at the item level. At a finer level, the shares of expenditure for the consumption segments in the item are applied. These shares are updated on an annual basis.

18.1.1.6. Compilation of total household final monetary consumption expenditure

The estimation of the total HFMCE for 2023 is consistent with the volume indices we derived from Quarterly Accounts data. It is based on the 2021 semi-definitive accounts from National Accounting and on the volume indices estimated with the Quarterly Accounts data for the whole 2022 year.

18.1.2. Prices

The price collection for the calculation of the consumer price index is carried out in different manners

• Part of the collection is carried out by INSEE investigators in the various physical sales outlets in metropolitan France and Dom. The INSEE regional services are responsible for this collection.
• Part of the collection is carried out on the internet: this collection can be carried out by agents of the regional directorates, by the Bordeaux price division, at the general direction or by institutional partners or their subcontractors (telecommunication and telecommunications prices, air transport). These collections can be manual or assisted by robots
• Some of the prices are extracted from private data (scanner data, medicines data).

Finally, administrative data are also used when they exist and are produced according to the CPI deadlines: National Sickness Insurance Fund data for health services and the fuel database.

18.1.2.1. Data Source - overview  

18.1.2.2. Scanner data - general information

Scanner data are used for the manufactured food products and cleaning and personal care products sold in supermarkets and hypermarkets since January 2020.

The Digital Technology Law (Law no. 2016-1321 of 7 October 2016 for a Digital Republic) provides for the regular transmission, by private retailers, of all data (quantity, price and turnover) relating to the sale of an article (EAN) in a retail outlet for supermarkets and hypermarkets.

18.1.2.3. Web scraping - general information

Insee has long used webscraped data for airfares but the webscraping was subcontracted. Insee has used its own robots for sea transport since 2016 and for train since 2020. The development of robots focused on transport services with few providers and a very high volatility of the prices in order to maximize the cost-effectiveness of the use of this new datasource. Moreover, in the case of services, the webscraped data are very well-structured and no issue of classification, identification and replacement occurs. In a second step, Insee develops robots for durable goods (computer, Smartphone) but they are used only to estimate hedonic models. The monthly calculation of the indices relies still on data collected on the field by price collectors.

18.1.3. Sampling

18.1.3.1. Sampling design: locations for survey

The price observations on the field are carried out in a random sample of urban units that are representative of urban units with more than 2,000 inhabitants throughout the country. 

18.1.3.2. Sampling design: outlets

The choice of retail outlets (approx. 30,000) in the sampled urban area is  made by the collectors according to a distribution per form of sale. This is known by professional sources. It is specific to each consumption segment and is decided at national level.

All forms of sale are represented. The classification of the index defines 11 forms of sale, hypermarkets, discount stores, supermarkets, mini-markets, variety stores, department stores, specialist stores, local shops, markets, provisions of services and other retail outlets (public services, special distribution channels (wine producers)). Online selling and distance selling are monitored at national level.

The sample of retail outlets is updated once a year, in December. When a shop closes down, it is replaced during the year by a shop of the same type in the same geographical area. The sample per type of shop is therefore fixed during the year.

18.1.3.3. Sampling design: newly significant goods and services

Multiple sources are used to identify new goods and services:

• feedback from collectors and managers who are best placed to observe the availability of products
• the latest news on professional websites such as GIFAM or Écho Touristique, or from market research institutes such as GFK or Nielsen
• the mass retail sector press
• National Accounting data
• the INSEE Household Budget Survey giving detailed figures per consumption item
• scanner data
• comparison with other European countries

In addition, the definition and technical specifications of certain products change in order to take account of considerations such as technical developments, especially for durable goods. The sample is reviewed on an annual basis.

Price data is collected every month.

18.3.1. Price collection surveys

18.3.2. Timing of price collection

The prices of goods are recorded in the month during which they are observed; the prices of services are recorded in the month during which the consumption of the service may begin.

However, for reasons relating to the availability of data, there may be a time lag in the observation of certain services mentioned hereinafter.

Heating networks: the records correspond to the invoices for month m-1. They are derived from the sample for the INSEE producer price index. The schedule for this indicator does not correspond to the schedule for the calculation of the CPI.

Telecommunication services: ARCEP (the French telecommunications regulator) only takes account of new offers, withdrawals of offers and changes in pricing after the modification has been effective for a period of 30 days.

This means that if a change during month m occurs after the 2^nd day, then this change will only be taken into account for the month m+1.

Medicines: The index is created on the basis of the IQVIA database. The data are only available and included in the calculation in month m+1.

Data are validated at different level of the statistical process: collection of the data, sample design, methodology.

18.4.1. Data validation - price data

With regard to quality control, numerous tools are made available to collectors, Price Site managers or the sector managers at Division level, in order to identify major changes in prices or unrecorded prices, verify the number of surveys per week or per retail outlet, prices that have remain unchanged for 13 months, and the diversity of brands, for example. For fresh products, a check of the weights entered by the collector is added to the aforementioned controls.

In order to identify products with potentially irregular changes, price ranges are calculated by sector experts each year on the basis of the price trends over the year Y-1. Prices that fall outside the range are automatically reported to the collector and then checked by the manager who is responsible for validating or rejecting the change. If the change is not validated, the price will either be corrected after a second survey or declared temporarily missing.

18.5.1. Elementary price index formulae

The HICP is an annually chained Laspeyres-type index which allows the weights to be changed on an annual basis.

The indices at the consumption segment level are calculated by the weighted sum of the elementary indices divided by the elementary indices for month 0 (December of the previous year); the weights correspond to the sampling weights of the urban units.

The prices are recorded as displayed in the retail outlets, generally to 2 decimal places and the weights are applied to 13 decimal places. The values are not truncated at the different calculation stages. However, the published indices are rounded up to 2 decimal places and the variations calculated on the basis of the published indices are rounded up to 1 decimal place

18.5.2. Aggregation of different data sources

18.5.3. Chaining, linking and splicing methods

The CPI and HICP are products of the chain-linking of the annual indices calculated according to the Laspeyres formula with the intermediate base being the month of December of the previous year.

Chain-linking is carried out at all levels of groupings.

18.5.4. Quality adjustment – Detailed information

Quality adjustments are carried out primarily in the framework of the replacement of products.

For field recordings, several methods are used according to the expertise of the collector, manager or sector expert:

• If the replacement product is considered to be a perfect substitute for the replaced product, then the replacement product will have the same base price as the old product. There is no 'quality effect' and the entire price difference is likened to a 'pure' price variation (direct price comparison method). In 2015, this method was applied to 44.0% of replaced products.
• If the replacement product is not considered to be a perfect substitute, then its base price is estimated according to the base price of the replaced product monitored in month m-1 and the change in prices between m-1 and m of products belonging to the same consumption segment as the replaced product for which observations are available (bridged overlap method).

In addition, if the collector knows the price of the replacement product in the month m-1 or in the month of December, the estimate will take account of this price.

The quality adjustment is applied to all products but especially to durable goods.

• A base price can also be estimated by hedonic models using the specifications of the replacement and the replaced product. This method requires a sufficient number of products in order to estimate the effects of each technical specification that contributes to the model. It is used for several durable goods (washing machines, dishwashers, refrigerators, televisions, computer, smartphone) and also for "best sellers".
• The Option pricing model has been adopted for replacements relating to new motor vehicles.

For scanner data, a paper was published in 2017 on the quality adjustment applied.

On a subset of 13 product families (food and manufactured goods), different techniques of quality adjustment were compared. Quality adjustment was found necessary. All quality correction methods tested in the paper lead to statistically-identical price indices.

Full paper available at https://www.insee.fr/fr/statistiques/fichier/2912650/F1704.pdf

18.5.5. Seasonal items

The standards of Commission Regulation (EU) No. 330/2009 relating to the processing of seasonal items, repealed and replaced by Commission Implementing Regulation (EU) 2020/1148, have been in application since 2011.

This regulation has led INSEE to make substantial changes to the calculation methods for the French Consumer Price Index (CPI) and the HICP for these products. A processing operation to estimate the change by means of an auxiliary index (the auxiliary index may be the group to which the consumption segment belongs) is applied to the last normal price observed.

The 'clothing-footwear' sector covers 70% of products which are totally unavailable for a period of the year. Therefore, these products will not be available on the collector's tablet computer.

The other sectors comprising seasonal items are the food sector (fruits, vegetables, fish and shellfish, etc.), the manufactured goods sector (garden furniture, etc.) and the service sector (ski rentals, etc.).

Not applicable.

None.