Reference metadata describe statistical concepts and methodologies used for the collection and generation of data. They provide information on data quality and, since they are strongly content-oriented, assist users in interpreting the data. Reference metadata, unlike structural metadata, can be decoupled from the data.
Construction material costs index (source: output price statistics on the domestic market). Labour cost index for construction activity (based on costs of hours worked, source: labour force statistics). Construction costs index for new residential buildings (in Slovenian: Indeks gradbenih stroškov za stanovanja). The main purpose of this indicator is to follow the evolution of contractors costs during the construction process.
3.2. Classification system
NACE rev.2
3.3. Coverage - sector
The indices cover the construction costs which relate to the units registered within the Section F of NACE Rev. 2, referring to the construction of residential buildings. Input data are indices already published for other purposes, so there is no special survey carried out for these indicators. The construction costs index (total) is calculated as a weighted arithmetic average of the material costs index (source: output (producer) price indices at the domestic market for construction materials) and the labour costs index (expressed in the form of the index of costs for hour worked, source: labour force statistics).
Construction material costs index: units employing more than 20 persons. Labour costs index: legal persons – all size classes are included. The following population is not covered by the labour costs index:
individual private entrepreneurs and persons in paid employment working for them;
persons engaged in public works;
deployed employed persons (posted workers);
own account workers;
farmers.
3.4. Statistical concepts and definitions
Prices for representative materials, within the price statistics, as well as the labour cost index from the labour force statistics, are collected.
List of the materials included in the construction costs material index. 4-digit code from the Prodcom list_2008. Description: 08.11: Ornamental and building stone, limestone, gypsum, chalk and slate 08.12: Gravel, sand, clays and kaolin 16.10: Wood, sawn and planed 16.21: Veneer sheets and wood-based panels 16.23: Other builders' carpentry and joinery 19.20: Refined petroleum products 20.16: Plastics in primary forms 20.30: Paints, varnishes and similar coatings, printing ink and mastics 20.52: Glues 20.59: Other chemical products n.e.c. 22.19: Other rubber products 22.21: Plastic plates, sheets, tubes and profiles 22.23: Builders' ware of plastic 22.29: Other plastic products 23.12: Shaped and processed flat glass 23.14: Glass fibres 23.31: Ceramic tiles and flags 23.32: Bricks, tiles and construction products, in baked clay 23.43: Ceramic insulators and insulating fittings 23.51: Cement 23.52: Lime and plaster 23.61: Concrete products for construction purposes 23.63: Ready-mixed concrete 23.64: Mortars 23.65: Fibre cement 23.69: Other articles of concrete, plaster and cement 23.70: Cut, shaped and finished stone 23.99: Other non-metallic mineral products n.e.c. 24.10: Basic iron and steel and ferro-alloys 24.31: Cold drawn bars 24.34: Cold drawn wire 24.42: Aluminium 24.43: Lead, zinc and tin 25.11: Metal structures and parts of structures 25.12: Doors and windows of metal 25.21: Central heating radiators and boilers 25.29: Other tanks, reservoirs and containers of metal 25.62: Machining services 25.72: Locks and hinges 25.93: Wire products, chain and springs 25.99: Other fabricated metal products n.e.c. 26.51: Measuring, testing and navigating equipment 27.12: Electricity distribution and control apparatus
For the labour costs index the variable is the cost per hour worked for the different types of work involved in the construction process. For the purpose of calculation of index of construction costs the data for labour cost index for section F construction are used. The following components of labour costs are included:
employee’s allowances;
employers’ social security contributions;
payroll taxes (eliminated on 1 January 2009);
and subsidies.
The following costs are not taken into account:
vocational training costs and other labour costs (recruitment costs and clothing).
3.5. Statistical unit
The observation units for the material costs index are the products needed for construction of new residential buildings according to the Prodcom list. For the labour costs index the units are legal persons of the public and private sectors or their units registered for performing activity in the Republic of Slovenia.
3.6. Statistical population
Reporting units for the material costs index are enterprises. In 2023 251 units reported prices for 799 products, from which construction materials index is calculated. For the labour costs index the units are all legal persons of the public and private sectors or their units registered for performing activity in section F (Nace Rev.2) in the Republic of Slovenia.
3.7. Reference area
The Republic of Slovenia.
3.8. Coverage - Time
Data are available from first quarter 2000.
3.9. Base period
2021
Index.
A Quarter.
6.1. Institutional Mandate - legal acts and other agreements
- European Business Statistics (EBS) Regulation (EU) 2019/2152 of the European Parliament and Council of 27 November 2019 and the Commission Implementing Regulation 2020/1197 laying down technical specifications and arragements pursuant to the mentioned EBS REgulation (General Implementing Act). The former legal basis for the STS indicators is the Council Regulation No 1165/98 of 19 May 1998 concerning short term statistics and subsequent amending regulations.
6.2. Institutional Mandate - data sharing
We do not send data directly to any other data producing agency except to Eurostat.
7.1. Confidentiality - policy
Regulation (EC) No. 223/2009 on European statistics (recital 24 and Article 20 (4)) of 11 March 2009 (OJ L 87,p.164), stipulates the need to establish common principles and guidelines ensuring the confidentiality of data used for the production of European statistics and the access to those confidential data.
All data collected and published by the Statistical Office are governed by the National Statistics Act (OJ) RS No. 45/95 and No. 9/01.
7.2. Confidentiality - data treatment
Only the aggregated data are published from which the single data values can not be recognized (secondary source of data).
8.1. Release calendar
The release calendar with advanced release dates for all quarters of the reference year is published at the beginnig of the year on a website of the Statistical Office of the RS. The release calendar is publicly accessible.
The most important information channel for data publication is the website http://www.stat.si/StatWeb/en. The Office publishes electronic and printed publications.The Office publishes several types of serial publications, different series and other publications which are according to the content intended for different users (e.g. general public, professional public, statistical experts). Data are available free of charge, except those data that are prepared on users’ request. Statistical data and information are always published at 10.30. All releases are announced at the Office’s website http://www.stat.si/StatWeb/en/ReleaseCal. The data are relased on the same date to all interested parties. None of the users have a prior access to the data. The release policy determines the dissemination of statistical data to all users at the same time. The simultaneous issue of the First Release is ensured. Data could be obtained on SURS website,via phone, mail, fax and e-mail and by visiting SURS Information Centre during office hours. Published data are simultaneously sent in electronic form to Eurostat. Same release policy applied to national release is applied to transmissions to Eurostat.
Construction costs indices are produced and disseminated quarterly.
10.1. Dissemination format - News release
The data on construction costs index for new residential buildings are published quartely at the Office’s website http://www.stat.si/StatWeb/en to release calendar, in the first release “Construction costs indices for residential buildings”. First data are issued with a notice called First Release at 10:30 a.m. on SURS website. First Release is available within 75 days after reference quarter. With releases in the First Release series the Office disseminates first and most important findings of statistical survey (construction material costs index, labour costs index and construction costs index - total).
10.2. Dissemination format - Publications
There is no paper publication.
E-release - First Release, quarterly (Slovenian, English), publishes: Construction costs indices for residential buildings.
10.3. Dissemination format - online database
Besides First Release, data series on construction costs indices are also available on the SURS website in the SiStat Database (https://pxweb.stat.si/SiStat/en) → Construction → Construction works and costs → Indices of construction costs:
SiStat Database provides a modern way of preparing and exporting data for selected categories.
10.4. Dissemination format - microdata access
In Slovenia, the entities entitled to obtain the statistically protected microdata include the registered research institutions, registered researchers, and the researchers of government offices. Basic instructions concerning the access and the use of statistically protected microdata are availabe on the website: http://www.stat.si/StatWeb/en/StaticPages/Index/For-Researchers.
10.5. Dissemination format - other
The data of construction costs indices are transmitted to Eurostat according to STS Requirements under NACE Rev. 2 for the dissemination of national data in Eurostat’s dissemination database.
10.6. Documentation on methodology
Methodological explanations for construction costs indices for residential buildings are availabe on the website: http://www.stat.si/statweb/en/mainnavigation/methods-and-classifications/methodological-explanations. There is an automatic link to the methodological explanations in the electronic version of the First Relase and at the SiStat Database for the data set on construction costs indices for residential buildings.
Theme: Construction, Sub-theme: Construction Works and Costs
10.7. Quality management - documentation
Not available.
11.1. Quality assurance
The Statistical Office of the Republic of Slovenia operates on the basis of the National Statistics Act and Regulation (EC) No. 223/2009 on European statistics; in performing its tasks it follows the general principles of quality management, the European Statistics Code of Practice and the Fundamental Principles of Official Statistics. In line with the stated, SURS declares that it takes into account the following principles: professional independence, process orientation, quality of products and services, planning of improvements, stimulating working environment for employees, data providers-friendly official statistics, user-oriented official statistics. Quality assurance policy and documentation can be reached on SURS websites: http://www.stat.si/StatWeb/en/FundamentalPrinciples/QualityInStat.
11.2. Quality management - assessment
Indices of construction costs for new residential buildings are produced in compliance with methodological requirements and standards. All statistics that are required by current Regulative are available. The publication schedule is fixed and announced in advance for the First Release. The data are published not later than 75 days after the reference quarter. Published data are final. All series are available from first quarter of 2000 onwards and are comparable and free of any breaks. Data are internally coherent. All results are displayed exclusively in the form of indices. Good comparability of data between countries and good quality of aggregates calculated from these data at the EU level is enshured.
12.1. Relevance - User Needs
Data are used by different users: Eurostat, government departments, trade unions, researchers, students, internal users, enterprises/businesses.
12.2. Relevance - User Satisfaction
The principle users are asked about their needs, wishes, and interests at the regular meetings, i.e. at the statistical advisory commite on construction statistics.
12.3. Completeness
All statistics that are required by current Regulative are available.
13.1. Accuracy - overall
Primary data - Labour costs: Unit Non-Response Rate: Variable used for the calculation of the weighted rate: The number of persons in paid employment who received earnings (average 8.9% non-weighted and 2.1% weighted in 2023). The item non-response is discussed in such a way so as to assign the missing data zero value, and is estimated only if such zero value is the reason the record „fails” at one of the logical controls. Such imputations are carried out during the phase of automatic data editing. The adopted concept can lead us to a consideration that there is no item non-response, and we therefore do not present the levels of item non-response. Average rate of the imputed data (imputed and edited data) for the gross earnings was 13.7% non-weighted and 4.6% weighted in 2023.
Primary data – material costs: Unit Non-Response Rate: Average unit non-response rate in 2023 was 1.78%. It can happen that a reporting unit goes bankrupt, is liquidated, changes its activity, etc. Such a reporting unit is replaced by a new one or various methods for estimating missing data are used. The item non-response rate for the survey was 2.75%. In case that the reporting units do not complete the questionnaire in full, they are contacted in the data collection and editing phase, and the missing data are obtained. Editing rate was 0.91%. If the unit cannot be contacted, various methods for estimating missing prices are used. Average share of the imputed prices in 2023 was 7.68%.
13.2. Sampling error
The survey is not conducted on the basis of a random sample, therefore there is no sampling error.
Sampling errors for the material cost index can not be calculated because the survey is not based on a random sample but on threshold sampling. Coverage Bias can not be calculated because the survey is not based on a random sample.
For the labour cost index the survey is not conducted on the basis of a sample, therefore the estimates do not include a sampling error.
13.3. Non-sampling error
Primary data - Labour costs: Over-coverage Errors: Variable used for the calculation of the weighted rate: The number of persons in paid employment who received earnings (9.9% unweighted in 2023).
Primary data – Material costs: Average over-coverage rate in 2023 was 0.54%. For the editing rate there is no precise record of corrections in the data editing phase, so the editing rate can not be calculated.
14.1. Timeliness
The publication schedule is fixed and announced in advance. The First Release is published 75 days after the end of the reference quarter. Data are at the same time also loaded into the SiStat Database on a website of the Statistical office of the Republic of Slovenia, created for user friendly free of charge data manipulation. Data are published as final.
14.2. Punctuality
There is no time lag between the actual delivery of the data and the target date when it should have been delivered. All news releases are published according to the announced release calendar.
15.1. Comparability - geographical
The statistics are in compliance with the STS requirements in the EBS Regulation and the EBS methodologic guidelines. This ensures a good comparability between national data and good quality European aggregates.
15.2. Comparability - over time
Time series of indices calculated according to the current methodology are available from first quarter 2000 onwards. Until the end of 2023, the length of the series is 96 quarters. On 1 January 2008 all Member States of the European Union launched a new classification of activities of business entities NACE Rev. 2, which replaced the existing NACE Rev.1.1. In Slovenia the national version of the standard classification, called SKD 2008, came into force. It includes the entire European classification of activities, but also adds national divisions. The new classification has brought many changes and additions that are the result of structural changes in the economy in recent years. Most changes are in market services and manufacturing. Another important change is in the structure of classification, because the revised classification eliminates the level of subsections (2-digit code).
15.3. Coherence - cross domain
No related statistical outputs. The results of the survey are not confronted with other data sets.
15.4. Coherence - internal
Data are internally coherent. High level aggregations are derived from detailed indices according to well-defined procedures.
In 2023 the number of working hours spent on the survey was 104. There is no burden on respondents due to use secondary source of data – already published indices for other purposes.
At the present time no changes are planned on survey.
17.2. Data revision - practice
All published data are final at time of beeing published. Changes and revisions of methodology are announced in advance. Due to change of the base year data is planned every five years.
18.1. Source data
Secondary source - indices were already published for other purposes. There is no special survey created for these indicators. The results (indices) of already existing surveys on output price indices for construction material costs index and labour costs index from labour force statistics. The construction costs index (total) is calculated as a weighted arithmetic average of the previously mentioned two components.
18.2. Frequency of data collection
Labour costs indices on the basis of costs per hours worked are available quarterly. Material costs indices are available monthly. Construction costs indices (total) are compiled from these two indices on a quarterly basis.
18.3. Data collection
There are no questionnaires and no survey carried out for these indicators – the results (indices) of already existing surveys on output price indices for construction material costs index and labour cost index from labour force statistics are collected. The construction costs index (total) is calculated as a weighted arithmetic average of the previously mentioned two components. We get the data extraction of both components (construction material costs and labour costs) in needed form and have no access to the database of primary surveys data sources. The data for construction material costs are monthly collected, recalculated to quarterly data and the data for labour costs are quartely collected and rebased on 2021.
18.4. Data validation
Data validation is made on primary source of data:
Material costs -verification of prices: Reporting units verify prices of the products by reporting prices for the current month. Changes, if any, have to be explained on the questionnaire. In addition, the Price Statistics Department performs (i) checking of prices on questionnaires (calculating percentage changes), (ii) control of data entry by comparing calculated monthly indices with the prices on questionnaires, and (iii) monthly telephone contacts with reporting units if the questionnaire was not completed properly. Verification of processing: Data entry and checking of prices is done in Blaise program. Calculation of indices is performed on a PC with SAS. All bases of prices and of indices are standardized in relation base of ORACLE system.
Labour costs: Reporting units reports hour worked for section F (Nace Rev.2). For legal persons that are involved in the calculation of labour cost indices missing data for two components are imputed: payroll taxes and social contributions. The criteria for imputing missing data are: i) The missing data for every legal persons that has no data for the social contributions variable are imputed; ii) In case the data for the payroll taxes variable are missing, first the average gross wage per person employed by a legal person is checked and if this is greater than the legally determined threshold for which the legal person has to pay tax, the missing data for the payroll taxes variable are imputed according to tax rates. The imputation of missing data is done on monthly data on labour costs.
Secondary source of data - the previously published indices for other purposes are validated and used in the survey Construction costs indices for residential buildings. The proces is estimated in Excel file.
We do not use special aggregates to sent data to Eurostat. Data which are published in the national publications are simultaneously sent in electronic form to Eurostat. Data are transmitted quarterly in .xml (SDMX) format via eDamis to Eurostat (since 2017).
18.5. Data compilation
Within the survey (on construction costs indices), only one variable is measured – cost. We use secondary source of data - the previously published indices for other purposes:
construction material cost index from output price statistics on domestic market;
and labour cost index from the labour force statistics.
The construction costs index (total) is calculated as a weighted arithmetic average of the previously mentioned two components. No other data compilation processes are made. Weights for the labour and material components are calculated from data of annual accounts. The weights are updated (calculated) every year. Data was recalculated in 2018 (calculated to the base year 2015). Data was last revised due to change of the base year in 2024 (the base year is now 2021).
18.6. Adjustment
No adjustment of indices is done.
No comment.
Construction material costs index (source: output price statistics on the domestic market). Labour cost index for construction activity (based on costs of hours worked, source: labour force statistics). Construction costs index for new residential buildings (in Slovenian: Indeks gradbenih stroškov za stanovanja). The main purpose of this indicator is to follow the evolution of contractors costs during the construction process.
14 June 2024
Prices for representative materials, within the price statistics, as well as the labour cost index from the labour force statistics, are collected.
List of the materials included in the construction costs material index. 4-digit code from the Prodcom list_2008. Description: 08.11: Ornamental and building stone, limestone, gypsum, chalk and slate 08.12: Gravel, sand, clays and kaolin 16.10: Wood, sawn and planed 16.21: Veneer sheets and wood-based panels 16.23: Other builders' carpentry and joinery 19.20: Refined petroleum products 20.16: Plastics in primary forms 20.30: Paints, varnishes and similar coatings, printing ink and mastics 20.52: Glues 20.59: Other chemical products n.e.c. 22.19: Other rubber products 22.21: Plastic plates, sheets, tubes and profiles 22.23: Builders' ware of plastic 22.29: Other plastic products 23.12: Shaped and processed flat glass 23.14: Glass fibres 23.31: Ceramic tiles and flags 23.32: Bricks, tiles and construction products, in baked clay 23.43: Ceramic insulators and insulating fittings 23.51: Cement 23.52: Lime and plaster 23.61: Concrete products for construction purposes 23.63: Ready-mixed concrete 23.64: Mortars 23.65: Fibre cement 23.69: Other articles of concrete, plaster and cement 23.70: Cut, shaped and finished stone 23.99: Other non-metallic mineral products n.e.c. 24.10: Basic iron and steel and ferro-alloys 24.31: Cold drawn bars 24.34: Cold drawn wire 24.42: Aluminium 24.43: Lead, zinc and tin 25.11: Metal structures and parts of structures 25.12: Doors and windows of metal 25.21: Central heating radiators and boilers 25.29: Other tanks, reservoirs and containers of metal 25.62: Machining services 25.72: Locks and hinges 25.93: Wire products, chain and springs 25.99: Other fabricated metal products n.e.c. 26.51: Measuring, testing and navigating equipment 27.12: Electricity distribution and control apparatus
For the labour costs index the variable is the cost per hour worked for the different types of work involved in the construction process. For the purpose of calculation of index of construction costs the data for labour cost index for section F construction are used. The following components of labour costs are included:
employee’s allowances;
employers’ social security contributions;
payroll taxes (eliminated on 1 January 2009);
and subsidies.
The following costs are not taken into account:
vocational training costs and other labour costs (recruitment costs and clothing).
The observation units for the material costs index are the products needed for construction of new residential buildings according to the Prodcom list. For the labour costs index the units are legal persons of the public and private sectors or their units registered for performing activity in the Republic of Slovenia.
Reporting units for the material costs index are enterprises. In 2023 251 units reported prices for 799 products, from which construction materials index is calculated. For the labour costs index the units are all legal persons of the public and private sectors or their units registered for performing activity in section F (Nace Rev.2) in the Republic of Slovenia.
The Republic of Slovenia.
A Quarter.
Primary data - Labour costs: Unit Non-Response Rate: Variable used for the calculation of the weighted rate: The number of persons in paid employment who received earnings (average 8.9% non-weighted and 2.1% weighted in 2023). The item non-response is discussed in such a way so as to assign the missing data zero value, and is estimated only if such zero value is the reason the record „fails” at one of the logical controls. Such imputations are carried out during the phase of automatic data editing. The adopted concept can lead us to a consideration that there is no item non-response, and we therefore do not present the levels of item non-response. Average rate of the imputed data (imputed and edited data) for the gross earnings was 13.7% non-weighted and 4.6% weighted in 2023.
Primary data – material costs: Unit Non-Response Rate: Average unit non-response rate in 2023 was 1.78%. It can happen that a reporting unit goes bankrupt, is liquidated, changes its activity, etc. Such a reporting unit is replaced by a new one or various methods for estimating missing data are used. The item non-response rate for the survey was 2.75%. In case that the reporting units do not complete the questionnaire in full, they are contacted in the data collection and editing phase, and the missing data are obtained. Editing rate was 0.91%. If the unit cannot be contacted, various methods for estimating missing prices are used. Average share of the imputed prices in 2023 was 7.68%.
Index.
Within the survey (on construction costs indices), only one variable is measured – cost. We use secondary source of data - the previously published indices for other purposes:
construction material cost index from output price statistics on domestic market;
and labour cost index from the labour force statistics.
The construction costs index (total) is calculated as a weighted arithmetic average of the previously mentioned two components. No other data compilation processes are made. Weights for the labour and material components are calculated from data of annual accounts. The weights are updated (calculated) every year. Data was recalculated in 2018 (calculated to the base year 2015). Data was last revised due to change of the base year in 2024 (the base year is now 2021).
Secondary source - indices were already published for other purposes. There is no special survey created for these indicators. The results (indices) of already existing surveys on output price indices for construction material costs index and labour costs index from labour force statistics. The construction costs index (total) is calculated as a weighted arithmetic average of the previously mentioned two components.
Construction costs indices are produced and disseminated quarterly.
The publication schedule is fixed and announced in advance. The First Release is published 75 days after the end of the reference quarter. Data are at the same time also loaded into the SiStat Database on a website of the Statistical office of the Republic of Slovenia, created for user friendly free of charge data manipulation. Data are published as final.
The statistics are in compliance with the STS requirements in the EBS Regulation and the EBS methodologic guidelines. This ensures a good comparability between national data and good quality European aggregates.
Time series of indices calculated according to the current methodology are available from first quarter 2000 onwards. Until the end of 2023, the length of the series is 96 quarters. On 1 January 2008 all Member States of the European Union launched a new classification of activities of business entities NACE Rev. 2, which replaced the existing NACE Rev.1.1. In Slovenia the national version of the standard classification, called SKD 2008, came into force. It includes the entire European classification of activities, but also adds national divisions. The new classification has brought many changes and additions that are the result of structural changes in the economy in recent years. Most changes are in market services and manufacturing. Another important change is in the structure of classification, because the revised classification eliminates the level of subsections (2-digit code).
