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For any question on data and metadata, please contact: Eurostat user support |
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1.1. Contact organisation | Croatian Bureau of Statistics (CBS) |
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1.2. Contact organisation unit | Macroeconomic Statistics Directorate Croatian Bureau of Statistics - Internal organisation (gov.hr) |
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1.5. Contact mail address | Ilica 3, 10000 Zagreb, Croatia |
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2.1. Metadata last certified | 28/06/2024 | ||
2.2. Metadata last posted | 28/06/2024 | ||
2.3. Metadata last update | 28/06/2024 |
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3.1. Data description | |||
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. |
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3.2. Classification system | |||
European classification of individual consumption according to purpose (ECOICOP) |
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3.3. Coverage - sector | |||
The HICP covers the final monetary consumption expenditure of the household sector. |
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3.4. Statistical concepts and definitions | |||
The main statistical variables are price indices. |
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3.5. Statistical unit | |||
The basic unit of statistical observation are prices for consumer products. |
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3.6. Statistical population | |||
See next points. |
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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. |
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3.6.2. Coverage error population | |||
All parts of the population are covered. |
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3.7. Reference area | |||
See next points. |
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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. |
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3.7.2. Coverage error regions | |||
The economic territory of Croatia is the same as the geographic territory. The HICP refers to the whole economic territory of Croatia consistent with NA (ESA 2010). No parts of the economic territory of Croatia are excluded from the index. |
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3.8. Coverage - Time | |||
See next points. |
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3.8.1. Start of time series | |||
The HICP series started in January 1997. |
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3.8.2. Start of time series - national specifics | |||
3.9. Base period | |||
2015=100 |
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The following units are used:
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HICP is a monthly statistics. |
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6.1. Institutional Mandate - legal acts and other agreements | |||
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 methodological documentation, namely recommendations and guidelines, is available in the HICP dedicated section, under 'Methodology'. |
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6.2. Institutional Mandate - data sharing | |||
None. |
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7.1. Confidentiality - policy | |||
Legal basis 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. In accordance with the Official Statistics Act statistical data on natural or legal persons, if these data can directly or indirectly be related to a natural or legal person, shall be deemed statistically confidential and shall represent an official secret. |
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7.2. Confidentiality - data treatment | |||
According to policy rules (see point 7.1). |
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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 Eurostat protocol on impartial access to Eurostat data for users. |
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8.1. Release calendar | |||
The release for the HICP follow a preannounced Calendar of Statistical Data Issues schedule which is publicly accessible on the CBS website. The HICP release schedule is the same as for the CPI. |
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8.2. Release calendar access | |||
8.3. Release policy - user access | |||
All publications, data and databases are announced in advance. A review of scheduled editions with a precise release date is available in the Calendar of Statistical Data Issues. A Calendar also allows users to see the announced dates of publishing as well as of those releases that have already been published. CPI and HICP are released in accordance with the plan announced in the Calendar, and are available on the website, precisely at 11 o'clock on the set date. Every potential deviation from the plan disclosed in the Calendar have to be previously announced with explanation is given including a new release date. No special users are granted special or pre-access to data. The CPI/HICP data are available in an equal manner and at the same time to all users. |
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Monthly. |
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The main channel for dissemination of the CPI/HICP is the CBS website: Croatian Bureau of Statistics - Home (gov.hr). The new website was launched in April 2022. Apart from the website, CBS uses other communication channels for dissemination: printed publications, electronic media, social networks. HICP index levels are disseminated with two decimal places and rates of change with one decimal place. All regular issues of publications released on the CBS website, and are available both in Croatian and English language. Still, CBS holds the right to publish special editions of publications in Croatian or English only. |
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10.1. Dissemination format - News release | |||
The HICP is published together with the CPI in the form of the first release, which is available on the CBS website: First release – Consumer price index |
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10.2. Dissemination format - Publications | |||
Except from the First release – Consumer price index, HICP is included in Statistics in line (on the CBS website). |
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10.3. Dissemination format - online database | |||
10.4. Dissemination format - microdata access | |||
Detailed HICP data is available on users’ request through User Communication Department. The CBS, upon a written request, allow scientists and scientific organisations that conduct statistical analyses for scientific purposes access to confidential statistical data that enable only indirect identification of a statistical unit may be granted exceptionally, based on a written request, for conducting statistical analyses solely for scientific purposes. The purpose of using statistical data is stated in the request. For the use of statistical data for scientific purposes, a special contract is concluded, according to which the user is materially and criminally liable, whereby the statistical data are used only for the purpose stated in the request, only authorized persons have access to the data, and data must be destroyed after use. |
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10.5. Dissemination format - other | |||
See also Eurostat's HICP website. |
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10.6. Documentation on methodology | |||
The HICP Methodological Manual provides the reference methodology for the production of HICP. |
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10.6.1. Documentation on methodology - national specifics | |||
Short description of methodology is published in every issue of the 'First release: Consumer Price Indices'. Written instructions like manuals and process documentation are available in Croatian. |
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10.7. Quality management - documentation | |||
The HICP Quality Reports are available on the CBS website: Quality reporting |
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The policy of the CBS is to continuously monitor and improve all statistical processes and products. CBS takes care not only about providers of statistical data but of users also. The European Statistics Code of Practice, together with other documentation, made available on CBS website, are used for quality developments and monitoring. Beside that CBS has developed POMI – Database of quality information which contains both quality concepts prescribed by Eurostat i.e. ESMS, ESQRS and SIMS (standard ESS metadata structures for quality reporting). The POMI is a central place for storing direct information on quality assessment and reference metadata. From this central place can be generated following information:
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11.1. Quality assurance | |||
See next points. |
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11.1.1. Quality management - Compliance Monitoring | |||
11.1.2. Quality assurance - national specifics | |||
In order to ensure the quality of price collection activities, a system of regular quality control of field collection has been established.
Price collectors are contacted on a daily basis in order to confirm the monitored prices and when necessary to revise incorrect price observations. Furthermore, price movements are checked for EAs and up to total index. |
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11.2. Quality management - assessment | |||
11.2.1. Compliance monitoring - last report and main results | |||
The last available compliance or follow-up report can be found in the dedicated HICP section ‘Compliance Monitoring’ of Eurostat’s website, under ‘Methodology’. |
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11.2.2. Quality assessment - national specifics | |||
The CPI/HICP Quality Reports are produced nationally and updated each year. The CPI/HICP Quality Reports are available on the CBS website: Quality reporting - Prices |
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12.1. Relevance - User Needs | |||
In addition to being a general measure of inflation, the HICP is also used in the areas of:
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. |
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12.1.1. User Needs - national specifics | |||
The main HICP/CPI users are national state institutions, other national users (financial institutions, economic analysts, the media, students, enterprises and the public), international institutions (Eurostat, ECB, IMF, UN ECE, etc.) and internal users (other statistical departments within the CBS). While the national CPI is preferred at national level, the HICP is mostly used for cross-country comparison of inflation between EU countries. |
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12.2. Relevance - User Satisfaction | |||
User satisfaction is measured by the user satisfaction survey of the CBS. The first user satisfactory survey was conducted in 2013, the second one in 2015, and the last one at the end of 2022. The survey was conducted online and detailed results for 2022 are available on the website of the CBS, on the following link: User satisfaction survey 2022. According to the 2022 survey results, of the total number of users who contacted the employees of the customer relations department, 70% of them agree (or completely agree) with the statement that the promptness of getting information is satisfactory. Furthermore, the same percentage of users are satisfied (or completely satisfied) with the information they received and agree (or completely agree) that the CBS employees are ready to provide help to users, while 90% of them agree (or completely agree) that it is easy to contact the CBS employees. Pursuant to Article 20 of the Official_Statistics_Act_2020 (Official Gazette, No. 25/20), the Statistical Council of the Republic of Croatia is established at the CBS. The Council is an advisory and expert body that deals with strategic issues of official statistics, which has been established to ensure the influence of users, science and the general public on the activities of official statistics. The members of the Council are nominated by institutions and bodies referred to in Article 22, paragraph 3 of the Act and appointed by the Government of the Republic of Croatia. |
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12.3. Completeness | |||
HICP and HICP-CT are in line with relevant regulations/guidelines. All ECOICOP categories accounting at least one part in a thousand of the total expenditure are calculated (HICP and HICP-CT) and transmitted to Eurostat. |
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13.1. Accuracy - overall | |||
The accuracy of source data is monitored by assessing the methodological soundness of price and weight sources and adherence of the methodological recommendations.
All private households in the economic territory of the country are covered, whether resident or not and irrespective of their income. There isn't any systematic errors and any revision of the data. |
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13.2. Sampling error | |||
Numerical estimates errors are not calculated because they are difficult to quantify due to the complexity of price index structures and due to use of non-probability sampling. The CBS tries to reduce the sampling errors by using a sample of consumer prices that is as large as possible given resource constrains. In order to minimise the variance of the total index, the number of prices that should be observed in each geographical location for each chosen item is selected. |
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13.3. Non-sampling error | |||
Non-sampling errors are not quantified. Non-sampling errors are reduced through continuous methodological improvements and survey process improvements which can help avoid coding and typing errors. |
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14.1. Timeliness | |||
The full set of HICPs is published each month according to a pre-announced schedule, usually between 15 and 18 days after the end of the reference month. Each year, the January news release is published at the end of February to allow for the annual update of the weights 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. |
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14.2. Punctuality | |||
Since the March 1997, launch of the HICP release, the HICP for the country groups aggregates has always been published on the pre-announced release dates. |
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15.1. Comparability - geographical | |||
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). |
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15.2. Comparability - over time | |||
HICP was introduced in 2007 and the main rescaling has been from 2005=100 to 2015=100 (since January 2016). The HICP data is 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 backward calculations under the newer standards were performed when appropriate basic data was available. |
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15.3. Coherence - cross domain | |||
Differences between the HICP and national CPI
Different data sources for the calculation of weights: |
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15.4. Coherence - internal | |||
The HICPs are internally coherent. Higher level aggregations are derived from detailed indices according to well-defined procedures. |
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Not available. |
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17.1. Data revision - policy | |||
The HICP series, including back data, is revisable under the terms set in Articles 17-20 of Commission Implementing Regulation (EU) 2020/1148. |
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17.1.1. Data revision - policy - national specifics | |||
The HICP series, including back data, is revisable under the terms set in Articles 17-20 of Commission Implementing Regulation (EU) 2020/1148. The users of statistical data are informed about revisions (provisional, final data) on the website of the CBS. The Flash estimate concerns to provisional data for the current month. This data is confirmed or revised with the final data within the second week of the following month. |
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17.2. Data revision - practice | |||
No cases of mistakes in the compilation of the total HICP that would require HICP revisions have arisen so far. Still, the change of reference year caused revisions to a number of previously published inflation rates because of rounding effects. Thus, inflation rates calculated from the 2015=100 series can differ from the rates calculated from the 2005=100 series. |
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18.1. Source data | |||
See next points. |
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18.1.1. Weights | |||
At ECOICOP 5-digit level, weights used in the current year are based on annual HFMCE data of the previous year, estimated in line with the domestic concept. HFMCE is obtained from provisional NA data for the first three quarters of the previous year. If no additional information is available, the 4th quarter of the t-1 is estimated by multiplying the 4th quarter of the t-2 values with the change between the first 3 quarters of the previous year (t-1) and the first three quarters of the year before (t-2). Below the ECOICOP 5-digit level, various sources are used for different product groups. Depending on the source, they are updated annually (i.e., telecommunication, new/second-hand motor cars, flights) or less frequently (depending on the HBS survey). Weights for the following year are reviewed and price-updated annually. The update of weights is done with the revision of the HICP basket of goods and services. |
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18.1.1.1. Compilation at elementary aggregate level | |||
The elementary aggregate is the lowest level of aggregation for which the weights are available (6th or 7th digit level). For product-offers within elementary aggregate, there are no weights available. The weighting structure follow the aggregation structure of the HICP (based on ECOICOP) and additional sub-sub-classes are introduced by stratification of the sample in order to obtain more detailed product level classification. Below the ECOICOP 5-digit level, weights are based mostly on the last available HBS data. Additional data sources for construction of the weights are. for electricity (the Croatian Energy Regulatory Agency), telecommunication services (the Croatian Regulatory Authority for Network Industries), insurance (the Financial Agency, the Croatian Insurance Bureau), cars (the Ministry of Interior), accommodation services (tourism statistics), transportation (transport statistics), education (the Ministry of science, education and sports as well as the education statistics), tobacco, fuels, medicines etc. At elementary aggregate level, weights are reviewed and price-updated on annually basis. Except for weights for elementary aggregates on the level of Croatia, there are regional weights as well (nine geographical locations included in the sample). Regional weights are defined at the elementary aggregate level – each geographical location in the sample as a pre-assigned weight (total sum of regional weights for each elementary aggregate is 1000). Elementary aggregates are weighted together by regional weights in order to obtain national elementary aggregates. These index numbers are then aggregated to the CPI/HICP. HBS data are available on the level of regions. As the prices for the CPI/HICP are collected in selected geographical locations representative for the certain region weights are allocated to the geographical locations - cities in the sample. In case where in a particular region only one city is included in the sample the weight of the region remains. On the other hand, where in a particular region, more cities are in the sample then regional weight is divided into cities according to the number of the population of these cities in the region (main source is the Census). Weights on the level of nine geographical locations are calculated for elementary aggregates for which prices are collected locally while for centrally collected prices there are no such weights (elementary aggregate indices are directly aggregated on the level of Croatia). No outlet weights are used. There are no weights associated with single price observations for product-offers. |
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18.1.1.2. List of elementary aggregates | |||
Restricted from publication | |||
18.1.1.3. Compilation of sub-index weights | |||
The HFMCE is calculated from the individual consumption expenditure of households minus narcotics, imputed rentals for housing, games of chance, prostitution, life insurance, health insurance, FISIM, net purchases abroad, and pensions. Compared to the previous year the largest increases in weights are found in division 11, Hotel and restaurants and in division 03, Clothing and footwear while the largest decrease in weights are found in division 4, Housing, water, electricity, gas and other fuels. |
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18.1.1.4. Price updating | |||
Price-updating to December t-1 is conducted by calculating price changes between the average of the t-1 and December t-1 (price reference period). Price-updating is applied at the elementary aggregate level. |
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18.1.2. Prices | |||
The main sources of price data are manual price collection (in shops, online, by telephone or email), web scraping, administrative data and catalogues. |
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18.1.2.1. Prices Data Source – detailed information | |||
Restricted from publication | |||
18.1.2.2. Price Collection Survey | |||
Restricted from publication | |||
18.1.2.3. Administrative data sources | |||
Restricted from publication | |||
18.1.2.4. Transaction data – general information | |||
CBS participated in the Eurostat Grant Agreement on scanner data with the general goal to undertake research on the exploitation of scanner data as new source of price information which would improve current methods. Analysis has been performed in the field of food and non-alcoholic beverages and alcoholic beverages and tobacco. So far, data from three retail chains have been obtained. As the methodology is finalised and the IT production system is established, all necessary preparations are performed in order to start the implementation of scanned data in the regular CPI/HICP production system. During the year 2024, a monthly test calculation in the new production system, using in parallel current methodology and new methodology, will be carried |
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18.1.2.5. Transaction data - detailed information | |||
See 18.1.2.4. |
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18.1.2.6. Web scraping - general information | |||
The implementation of web scraping in regular production started with the January 2021 index. ECOICOPs for which web scraping is applied:
Data for 33 products are web scraped twice a month (1st and 2nd Tuesday) from 13 websites of which 12 are physical stores and 1 are online store. In addition, prices for market rentals are web scraped from one (the most relevant) websites. Shot-term plan is to increase coverage regarding number of shops within the existing products, and medium-term plan is to increase the product coverage (hotels and apartments). Foreign websites are not included. Web scraping is used both to represent e-commerce (online shopping) and as a proxy for price collection in physical shops. |
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18.1.3. Sampling | |||
Within each statistical region geographical locations where survey price collection takes place are selected by applying the population number criterion based on the Census and the representativity for each statistical region (all regions are covered). Regional indices are not published. As there is no relevant data that would allow the application of outlet sample design based on one particular sampling method, judgmental sampling is applied (non-probability sampling method). Outlet sample is updated annually (usually in December). In addition, when in a certain month an outlet closes or is no longer representative or permanently closed, it is replaced in that same month. Different types of outlets are included in the sample:
The sample of products is based on the HBS data. Products with the significant expenditure share of the total expenditures of the reference population are included in the sample. Based on the pre-defined basket, specific product offers are selected and the as well as the related set of additional product characteristics that has to be recorded. The sample of product is updated annually and the reference product-offers in the outlet are updated monthly. |
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18.1.3.1. Sampling design: locations for survey | |||
Prices are collected in nine geographical locations: Zagreb (capital city), Slavonski Brod, Sisak, Osijek, Rijeka, Pula, Split, Dubrovnik and Varazdin. Geographical locations within each statistical region are selected by applying the population number criterion based on the Census and the representativity for each statistical region (all regions are covered). Although the geographical locations sample changes less frequently than the outlet sample or product sample, the availability of more recent data sources relevant to the existing geographical location sample are also taken into account. For that reason, analysis of the representativity of the geographical sample is done at the time of re-basing. Regional indices are not published. |
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18.1.3.2. Sampling design: outlets | |||
As there is no relevant data that would allow the application of outlet sample design based on one particular sampling method, judgmental sampling is applied (non-probability sampling method). The number of outlets that should enter the sample are determined by central office. The number of outlets for each representative product in each geographical location is pre-determined by the criteria of the population number for each geographical location (city) in the sample and regional weights - HBS data on the level of regions allocated to the cities. If only one city is included in the sample of a particular region, the weight of the region remains, and where more cities are in the sample of a particular region, the regional weight is divided into cities according to the number of the population of these cities in the region (main source is the Census). In total, 15 outlets are selected for one geographical location, Zagreb (leading to 15 price quotes for each representative product), 8 outlets for three geographical locations (leading to 8 price quotes for each representative product), 6 outlets for two geographical locations (leading to 6 price quotes for each representative product) and 4 outlets for two geographical locations (leading to 4 price quotes for each representative product). |
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18.1.3.3. Sampling design: products | |||
First, products that enter the sample are selected and in the second stage is the selection of the individual products for which the prices will be observed. The sample of products is based on the HBS data with the concept of HFMCE and with the method of representative product. Products have to be selected in the sample once its expenditure share exceeds 1/1000 of the total expenditures of the reference population. Then, within each selected group of products several individual products are selected. The set of individual products for the price survey are defined according to the weight of a product in the total consumption expenditure and continued availability on the market (except for seasonal products). Price collectors select particular product-offer in a particular outlet. The selection of a particular product-offer is done according to the criteria of the most sold product in the outlet. Since it is very important that the same product-offer is recorded each month, there is also a pre-defined set of additional product characteristics that has to be recorded by price collectors for each product offer. Additional product characteristics help price collectors to find the particular product offer next time visiting the outlet and, on the other hand, it helps the central staff when evaluation of quality differences is needed and in cases when price collectors are replaced. |
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18.1.3.4. Sampling design: newly significant goods and services | |||
Introducing newly significant products relates to the replacement of the goods and services from the basket which disappeared from the market with the ones which entered the market or to introducing completely new goods and services as such. New products on the market are identified mainly through the Household Budget Survey but also through other sources such as press (newspapers, magazine), producer information, PPP product list, market research, price collectors’ suggestions and other sources. Price collectors are instructed to monitor development in the market to identify new good and services and report these changes and tendencies for future changes to the central offices. The procedure of reviewing the product sample includes involvement of central staff and price collectors. While central staff is in charge for defining initial sample framework from the HBS results and additional alternative data source, price collectors provide the CBS with relevant information based on their experience and give the proposals regarding inclusion of new representative items or exclusion of existing ones as well as proposals on the changes of the existing product descriptions. Those proposals are sent each year, usually in October to central office where they are analysed. Reference product-offers in the outlet are selected by price collectors and they are updated monthly. Price collectors are instructed to select product-offers that are most sold in the outlet in accordance with pre-defined product description for the representative item. Selected product-offers are then checked and verified during the validation procedure in central office. For the newly introduced products, price collectors have to record prices for January of the current year and for December of the previous year (base period for prices in the current year). In the 2024 the following goods and services are introduced in the basket:
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18.2. Frequency of data collection | |||
Price data are collected every month. |
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18.3. Data collection | |||
Survey data collection: Each month, prices are collected by price collectors in outlets throughout the country (regional/field price collection). Electronic devices are used to register prices and all required information for each product. Prices are also collected centrally for passenger transport by air/train/bus, newspapers and periodicals, tobacco products, post and telecommunication services, package holidays, fuel prices, electricity, natural gas, bank and postal services, new and second-hand motor cars, accommodation services in camps, hostels, holiday apartment rents etc. Centrally collected data are recorded by telephone, Internet, catalogues or email. |
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18.3.1. Timing of price collection | |||
The regional (field) prices collection for the most goods and services take place once a month from 6th to 20th calendar day. The prices of fresh fruit and vegetables at market places are recorded on the first and the third Friday in the month. For certain products for which prices are recorded centrally prices are collected during the whole month (e.g. fuel for passenger cars) and for some of centrally collected products (hotels, package holidays and flights) prices are collected in advance, before the actual consumption of the service. |
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18.3.2. Devices for price collection | |||
Electronic devices for field price collection are used since January 2018 (Implementation based on a Eurostat Grant Agreement, November 2015 - August 2017). Each month, price collectors download the list of product-offers for which prices have to be recorded (the list is based on the last validated data from the previous month). Prices are organised according to the outlets that must be visited. Price collector can access the price history (12 months history) and the product description. Special codes are used to explain price movements. After price collection in the outlet is completed, prices are uploaded and transmitted to the central office database electronically. |
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18.4. Data validation | |||
Microdata validation is performed at different levels of the organisation (supervisors, regional offices, and central office). The software system at the local and central levels provides tools for regular validation. Extreme and unusual price changes are analysed in detail, with special attention to tariffs and regulated prices. Prices that remain stable for a long period are also checked. Final data are checked for internal consistency and completeness. Output files show the annual and monthly rates of change for elementary aggregates and the contribution to the index (in percentage points). |
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18.4.1. Data validation - Survey data | |||
First validation is done by the regional offices. During the price collection period, each price, quantity or product description change have to be stored in tablet computer with appropriate code (price increase/decrease, replacements, reductions/seasonal sales, product-offer not found in the outlet, change in quantity). The software also validates data with arithmetic operations by giving warnings about allowed price oscillation and code type input (additional confirmation is required). Review of historical data (one-year period) of selected product from previous months/periods is available in tablet computers as well. Prices are subsequently edited and validated again at the central level (compared to the previous month for each geographical location and for each item and outlet). For the purpose of price validation, a special data control program has been developed which performs several logical and arithmetical validation options in order to identify unusual price movements (except for percentage change in price for each product-offer comparing the previous month, the tool indicate if there is any change in quantity, code or product description) as well as the missing prices and replacement products. The tool indicates price movements for each product-offer in the last 12-months and prices for the same product-offer in other outlets or in other geographical locations. There is no automatic rejection and when further explanations are necessary or when errors have been detected central staff then requires from price collectors to provide additional information or to visit outlet again. In addition, field inspections (in regional offices) check and confirm both outlets and product specifications and they are carried out once a month (based on the sample of outlets and products). Prices that remain stable for a long period are checked as well. After the validation of prices is completed, software produces price indices comparing to the previous month showing the price movements on the level of individual representative items in the analysed geographical location or on the level of the whole country as well as the average prices for the individual representative items. For analytical purposes, verification tool also enables the export of different kind of summarised tables in Excel, depending on the purpose of analysis (i.e. separate tables with missing prices, tables showing only product with difference in prices or quantities, codes, product-offer descriptions, seasonal products, replacement products, comments or table containing all joined table containing all this information together). |
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18.4.2. Data validation – Transaction data, web scraping and large administrative data | |||
Validation procedure for web scrapped data includes standard data validation procedures (e.g. extreme outliers, number of records and items). |
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18.4.3. Data validation - Weights | |||
As regards weights, the plausibility is checked in a way that significant differences from the previous year are detected and cross-checked. Also, various additional data sources for weights are used and compared (where possible). Finally, the additivity of the weights is checked as well that total weight is 1,000. |
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18.4.4. Indices | |||
Mathematical plausibility checks are carried out in the production environment (e.g., higher level indices have to equal the weighted sum of lower-level indices when rebased to December). Large deviations in indices must be manually confirmed as well as indices that have not shown a price movement in long term. |
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18.5. Data compilation | |||
The HICP is Laspeyres type index, covering the categories of the ECOICOP/HICP. The price indices for elementary aggregates are calculated as a ratio of geometric mean prices (Jevons price index). The following rules are used for the number of decimals:
From above listed cases round half away from zero is used for rounding. |
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18.5.1. Elementary price index formulae | |||
Elementary aggregate indices are computed as a ratio of the current and the price reference period geometric mean (Jevons) of all prices of the products within an elementary aggregate. This index takes into account substitution effects, and it is indifferent to the price level of the observations. |
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18.5.2. Aggregation of different data sources | |||
Elementary aggregates are compiled as ratio of the geometric mean of prices for each region (for example Rice in Zagreb, Rice in Dubrovnik, Rice in Split etc.). It means that prices for product offers within elementary aggregate in the current month are compared to the prices of the base period (December of the previous year). Calculated elementary indices on regional level are then weighted together using regional weights in order to obtain elementary aggregate at national level. Regional weights are actually weights for each of 9 cities in which prices are collected and total sum for Croatia is 1,000. Elementary aggregate indices at national level are aggregated to higher index level using the Laspeyres’ type formula. |
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18.5.3. Chaining, linking and splicing methods | |||
The compilation of the HICP follows the chain linking method, with December of the previous year as the base. Following this process, each index is converted to reference year 2015 = 100. The splicing in the time series is not used. |
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18.5.4. Quality Adjustments and replacements | |||
Quality adjustment procedure used in the CPI/HICP:
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18.5.5. Seasonal items | |||
Seasonal products are treated according to the requirements of the Implementing Regulation (EU) 2020/1148. Minimum standards are applied to seasonal products within the following ECOICOP classes and groups:
Strict annual weights are used or determining the weights for seasonal items, i.e., the indices of seasonal items are calculated with fixed weights during the whole year. Therefore, estimated prices are applied for seasonal items that are out-of-season. |
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18.6. Adjustment | |||
See next point. |
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18.6.1. Seasonal adjustment | |||
The HICP is not seasonally adjusted. |
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None. |
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