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.
The objective of the Import Price Index is to measure the monthly evolution of the prices of those industrial products from the rest of the world.
3.2. Classification system
The Statistical Classification of Economic Activities in the European Community, Rev. 2 (NACE) for activities (to 4 digit-level) and the Combined Nomenclature and Statistical Classification of Products by Activity in the European Economic Community.
For disseminating data the Main Industrial Groupings classification (MIGs) is also used.
3.3. Coverage - sector
The Industrial Price Index covers sections B,C and D (Mining and quarrying, Manufacturing and Electricity, gas, steam and air conditioning supply) of the Statistical Classification of Economic Activities in the European Community, Rev. 2 (NACE,Rev. 2).
3.4. Statistical concepts and definitions
Aggregate index
Weighted arithmetic mean of elementary indices.
Basket of products
Set of products whose price is monthly collected.
Contribution
The contribution of a product is the extent to which the overall index changes when there are price changes only for that product (that is, all other prices remain constant).
Elementary index
Ratio of average prices in the current month to average prices in December of the previous year (multiplied by 100). Indices are unitless and measure price changes from the base period to the current month.
Import prices
Prices included in the index are producer prices with the following characteristics:
they are the prices existing at the national border, excluding VAT, other indirect taxes or customs duties, even though all sales or discounts are included. They are CIF prices (cost, insurance, freight), excluding transport or insurance costs relating to the part of the journey within Spain
they are current prices on 15th of the month
the currency is Euro. If the price is provided in a different currency, prices are exchanged to Euros.
Quality adjustment
Estimation of the price difference between the new (replacement) product and the old (replaced) one that is due to the quality change
Quality change
Change that occurs when the new product (variety or model) that replaces a previously selected one presents a change in its specifications that results in a significant difference in the utility of the product.
Rates of change
They show price developments between two periods of time.
Subvariety
Specific model of a product, in a concrete industrial establishment, whose price is collected monthly.
Weights:
Product weight is the relative importance of each product in the basket. Weights are calculated using the turnover from imports coming from Intrastat and the Single Administrative Document (SAD).
3.5. Statistical unit
Local units which import industrial products in Spain. The observation units are the same as the information units.
3.6. Statistical population
The target population is all local units which import industrial products in Spain.
The frame is the Custom Data.
3.7. Reference area
The whole national territory is covered except the Autonomous Cities of Ceuta and Melilla.
A breakdown by market is calculated, distinguishing between the Euro and the non-euro zone. The list of euro-zone countries is updated every time a new country joins the euro-zone.
3.8. Coverage - Time
The import price index is produced on a monthly basis and its results are available since January 2005.
3.9. Base period
Base period
The index reference period or base period is 2021=100.
Price reference period
Since the import price index is a Laspeyres chain index, monthly elementary indices are compiled as the ratio of current prices to prices of December of the previous year. Therefore the price reference period is December of the previous year.
Weight reference period
In the current year, weights have been compiled based on the 2021 import data and they have been updated with price information to December of the year immediately prior to the considered. Weights are updated yearly.
Indices
Indices are compiled as ratios of prices in a given month to prices in the reference month (December of the previous year) multiplied by 100. Therefore indices are unitless.
Rates of change
All rates of change are usually given as percentage changes.
Weights
For each item or group of items, weights represent the corresponding percentage share of the total value of imports.
The reference period for data is the month, in particular day 15th.
6.1. Institutional Mandate - legal acts and other agreements
The legal basis for the STS indicators are Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics, repealing 10 legal acts in the field of business statistics (EBS-Regulation) and Commission Implementing Regulation 2020/1197 laying down technical specifications and arrangements pursuant to Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics repealing 10 legal acts in the field of business statistic (General Implementing Act).
Before the EBS, the STS legal base was Council Regulation No 1165/98 of 19 May 1998 concerning short-term statistics, amended by Regulation No 1158/2005 of 6 July 2005 concerning short-term statistics. The Article 25.3 of Regulation (EU) 2019/2152 mentions that Regulation (EC) No 1165/98 is repealed with effect from 1 January 2024.
The definitions of short-term statistics variables are laid down in Commission Regulation No 1503/2006 of 28 September 2006 implementing and amending Council Regulation No 1165/98 of 19 May 1998 that concerns short-term statistics as regards the definition of variables.
According to the Spanish legislation, the Import Industrial Price Index is a compulsory statistic. It is based on the Royal Decree 410/2016 that establishes the approval of the National Statistical Plan 2021-2024 and Law No 12/1989 of the Public Statistical Function.
Laws 4/1990 and 13/1996 establish the obligation to provide data for the compilation of statistics included in the National Statistical Plan. Penalties for non-response range from EUR 60.10 to EUR 30,050.61.
6.2. Institutional Mandate - data sharing
INE makes available all the non-confidential data on its dissemination website.
Import price indices are transmitted to Eurostat every month, in order to produce the aggregates for the European Union and the Monetary Union.
7.1. Confidentiality - policy
The legal act Ley de la Función Pública, Chapter III on Confidentiality.
All users have access to the data at the same time by using the press release called 'Import and Export Price Indices for Industrial Products'. The data are posted on the Internet web site of INE immediately after the press release is issued.
Customised requests are also sent to registered users.
Following the recommendations of Eurostat and the European institutions, the INE is developing systems for systematic quality assessment of all statistical products and processes.
In the INE website, reports and quality indicators of each statistic are published (fields 11 to 19): Standardised Methodological Report
11.1. Quality assurance
The quality assurance framework for INE statistics is based on the ESSCoP, the European Statistics Code of Practice. The ESSCoP consists of 16 principles, grouped into three areas: Institutional Environment, Process and Products. Each principle is associated with a number of indicators to measure.In order to assess quality, different tools provided by Eurostat are used: the indicators mentioned above, the self-assessment (DESAP), peer review, quality audits and user satisfaction surveys.
The Import Price Indices of Industrial Products have a process designed to control and validate data quality throughout the entire process. There are validation controls in the electronic questionnaire, a data checking process in collection units and a control from the developer unit to ensure the quality of the statistic.
11.2. Quality management - assessment
Import Price Indices are indicators with big statistical quality that meet all the criteria of consistency, comparability, accuracy and timeliness. The methodology follows the recommendations of " Export and Import Price Index Manual: Theory and Practice", published by the International Monetary Fund (IMF) and agreed internationally.
The entry into force of the Base 2021, in January 2024, has been a methodological improvement as it has expanded the coverage of the branches studied and the basket of products; additionally, the weights have been updated to improve representativeness. Index are still chain indices thanks to that, modifications may be made in the sample each year, which will ensure that the indices remain updated.
12.1. Relevance - User Needs
The main users are:
ministries and other public organisms
autonomous Communities
companies
researchers and universities
press
foreign users, so much institutional as individuals. Between the first ones they stand out, Eurostat, the European Central Bank and the OECD.
Among the main uses is worth noting:
direct use as an indicator for the analysis of the economic activity linked to foreign trade. It provides information in order to monitor monthly prices of different groups of products and markets (Euro zone, Non-euro zone). It is also a useful tool for analysts and companies to analyze certain products of markets
indirect use as a deflator, in foreign trade statistics and national accounts.
12.2. Relevance - User Satisfaction
INE has conducted general surveys of users satisfaction in 2007, 2010, 2013 and 2016, and plans to continue doing so. The purpose is to know the perception of users regarding the quality of the information they use and whether their needs are covered.
Users’ specific needs are taken into account when methodological revisions are carried out in order to tailor the content of the survey to the specific requirements of its users, thereby increasing their levels of satisfaction.
In the Import Industrial Prices Index base 2010, the requests of information made by users were taken into account and INE started to publish data to a more detailed level of the classification. The dissemination of results disaggregated for Eurozone and non-Eurozone at the division level will begin in the base 2021.
12.3. Completeness
All levels of NACE Rev. 2 indices are produced, to 4-digit level although only 2-digits level indices are disseminated.
The rate of mandatory statistical available results, for the import price indices, is 100%.
13.1. Accuracy - overall
The accuracy is tackled at national and market (euro and non-euro zone) levels by eliminating non-sampling errors as much as possible and studying and analyzing revisions.
The main sources of error are non-response and overcoverage. There is no evidence that the response rate is distributed in a way that generates a bias in the index or its evolution. In addition, steps are taken to improve the updating of the sample, replacing, in a more agile way, units that have been deleted from the sample for new ones.
Due to the timeliness of the survey there is a non-response rate of 10%, at the time of the initial release. The questionnaires keep being required three months after the end of the reference month. This way new questionnaires are recorded after the first publication of the results and the non-response rate decreases. Another consequence is that the published results are updated monthly including both new and edited data.
Since the cut-off sampling is used, best sampling method to be used taking into account the skewness of the distribution of the Industrial businesses size in Spain, the estimation is biased, although there is no information about how much.
Data editing consists on several phases throughout the process. The first one is microediting and takes place during the data collection. The e-questionnaire contains workflows and several hard and soft edits. It makes possible that the data are cleaned by the respondent and there is no need to recontact. Finally the macroediting phase occurs, for the purpose of checking the results to be published.
During the whole data collection process the response rate is checked and attention is paid to get the data of the influential units.
13.2. Sampling error
As a non-probability sampling is used, it is not possible to obtain sampling errors.
The sample is based on the cut-off method, which, given the nature of the sector, is considered the most appropriate.
The Import Price Index has a sample of approximately 5,200 local units and it includes around 2100 products. The products in the sample represent the 80% of the total imports.
The cut-off method is applied at product level, firstly products are included depending on the production value of the product within the class to which they belong, covering up to 60% thereof, in those weighing over 0.1%, and covering up to 40% in the remainder. In each product, the enterprises with more value of import are selected (according to foreign trade data).
Revisions are made periodically with the aim of reaching 60% of coverage in production value in each activity of NACE Rev 2 as compared to the total estimated production value in the Industrial Products Survey. Aggregating activities MIGs are obtained, so keeping the coverage of the turnover in each activity assures the coverage in MIGs.
The sample is updated monthly in order to replace the products’ subvarieties of those local units that no longer produce them.
13.3. Non-sampling error
Different controls of non-sampling errors are carried out throughout the whole process.
Coverage: survey framework contains local units whose main activity is included in sections B to D of NACE, Rev2. It is updated annually. Overcoverage rate can be estimated as the units in the sample that are duplicated, unreachable, final closures and wrongly included. It reached 0.5% in 2024. Overcoverage is minimised by deleting the units mentioned before and under-coverage is minimised by including the new units in the framework.
Total non-response: In 2024, the non-response rate is 5.7%. The measures taken to reduce the non-response rate are: e-mail recontact to those informants who have not answered 7, 12 and 17 days after the end of reference month, increasing the period of data collection (not delaying the press-release day), sending specific information to those local units that provide information through the web questionnaire and request it and carrying out a more thorough follow up of the most influential units during the collection phase.
Partial non-response: Due to the data collection instrument, the short length of the questionnaire and the sample being a panel, the partial non-response is negligible.
Imputation: In order to correct the non-sampling errors, due to a lack of response or quality change, imputations and quality adjustments are carried out (see point 18.5)
Data editing: a first editing phase, at micro-data level takes place when the respondent fills in the e-questionnaire. Finally the macro-data editing phase takes place.
Coding: Identification variables are obtained from the survey frame and coded according to the NACE Rev 2. The products’ subvarieties are coded according to the Combined Nomenclature based on the information provided by the informants.
Estimation models: Not applicable (Estimation models are not used).
14.1. Timeliness
As established in the Regulation, the deadline for the data transmission is 45 days after the end of the reference period.
This deadline is met, since the results are published one month and four days after the end of the reference period, unless there is a public holiday. In this case, the results are published the previous working day.
14.2. Punctuality
Results are published in accordance with the release calendar for short-term business statistics (calendar).
The Import Price Index of Industrial Products has always been published on the pre-announced release dates.
15.1. Comparability - geographical
The comparability between EU countries is ensured by the EBS-Regulation (Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics, repealing 10 legal acts in the field of business statistics) and its General Implementing Act (Commission Implementing Regulation 2020/1197 laying down technical specifications and arrangements pursuant to Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics repealing 10 legal acts in the field of business statistic). They provide these statistics with homogeneity regarding the rest of European Union countries, which disseminate the same information on their respective industrial sectors.
15.2. Comparability - over time
The Import Price Indices of Industrial Products were published for the first time in January 2005. Since then there has been a change in the used classification and another one in the base year.
Since January 2009, the Statistical Classification of Economic Activities in the European Community, Rev. 2 (NACE-Rev. 2) is used. Indices are available since the beginning of the series with the new classification.
The change of base has led to changes of some of the methodological aspect of the survey, which have led to a break in the series that has been suitably treated to provide linked series from the first year of publication of the survey to the present date. Thus, the time series are comparable since their beginning in January 2005.
15.3. Coherence - cross domain
The Import Price Index of Industrial Products is consistent with Industrial Producer Prices (PPI) because they are designed in the same way and they use the same methodology.
15.4. Coherence - internal
The Import Price Indices of Industrial Products are internally coherent. Higher level aggregations are derived from detailed indices according to well-defined procedures.
The estimated cost to produce this survey in 2024 is 409.85 thousand euros.
In order to significantly reduce the burden on respondents, large companies that complete multiple surveys in one year are assisted from a special unit which coordinates all their questionnaires. The statistical burden on reporting units is taken into account when changes are performed on the sample, in order to avoid overloading the time dedicated to its completion.
In 2024, the burden of the Import Price Index was 17416 hours per year. The cost and burden are due only for STS needs.
17.1. Data revision - policy
Revised data are used both for the National dissemination and to obtain the STS data transmitted to Eurostat, so the same policy is applied to the STS data released nationally and sent to Eurostat.
The revision policy encompasses several types of revisions:
Routine revisions and errors are corrected within three months since its first publication.
Major revisions are performed on the occasion of rebasing or methodological changes like changes in definitions and classifications as well as legal changes like those due to new Regulations or updates in the already existing.
The differences registered between the provisional and the final data are due to the unavailability of the data in the provisional publication because of a late receipt of the questionnaire.
To measure the degree of variation between the provisional and the final results, changes between the first and the final publication were analyzed for the period between January 2022 and December 2024. The results are:
Year-on-year growth rates:
mean absolute revision (MAR) = 0.075
relative mean absolute revision (RMAR) = 0.544%
mean revision (MR) = -0.017.
18.1. Source data
The data used to calculate the Import Price Indices of industrial products are obtained by surveys of establishments. The frame of the survey is all establishments that have imported industrial products. The frame of the survey is the State Tax Office Foreign Trade database.
The criteria used to define which activities are part of the calculation of Import Price Index, base 2021, are: for the entire country, classes (4 digits NACE Rev. 2) that exceed 0.1% of the total turnover of the industry, and for the markets (Euro zone and non-euro zone), divisions (2 digits CNAE 2009) which exceed 1.0% of the total turnover of the industry in each market (according to the data of Customs in 2021).
In the Import Price Indices of industrial products, base 2021, around 19,000 prices of 2,100 products in approximately 5,200 establishments are monthly collected.
18.2. Frequency of data collection
Prices are collected once a month. The reference period for the data is day 15th of each month.
18.3. Data collection
Price collection is done through a questionnaire to industrial establishments that are part of the sample. Most respondents (80%) fill in the questionnaires through IRIA (data collection application via Internet), while the rest are completed by email, fax, telephone or mail.
The questionnaire lists the products for which the industrial establishment must include the price, with a detailed description of their characteristics, allowing the company to identify the exact product.
18.4. Data validation
In each collection unit all information requested in the questionnaire is checked and all incidents related to enterprises, establishments, subvarieties and prices are properly justified and explained. Next, a centralized data cleaning is done, in order to detect possible errors or unjustified price changes.
18.5. Data compilation
Data checking
As a general rule, respondents are recontacted in order to justify or correct any anomaly detected in the subvarieties or their prices during the validation process, in case they have changed the characteristics (both physical and commercial) or the unit of measure of the subvariety.
Index Calculation
First, the elementary indices are calculated as a ratio of the geometric mean of the prices collected in the month between the prices reported in December last year.
Subsequently, the elementary indices are aggregated using a weighted arithmetic mean.
Weights
The main source for the weights of the Import Price Indices of Industrial Products is Intrastat data and the SAD .
There are weights for each product in each market (Euro zone - rest of the world).
Treatment of missing items
When occasionally the product price has not been reported, the establishment is contacted to see if they can estimate the price that the transaction would have had.
If this is not possible, the price is estimated using the average change of the rest of prices collected for the same product or the corresponding branch in the same market.
Treatment of replacement products
When a subvariety disappears, INE contacts the informant to know if it is something temporary or permanent. In the event that the disappearance is permanent, the subvariety is to be replaced by another item of the same product.
In case the establishment does not have a substitute for the product, we try to find another establishment to provide information.
Adjustments for quality change
When there is a change in the specifications of a subvariety or it disappears and it is replaced, a quality adjustment must be done in order to determine the share of the price difference that is due to a quality change.
In general terms, estimated prices are used to make this adjustment. This method involves the estimation of a relative price change as the average price change of the aggregate that contains the subvariety (product or class).
18.6. Adjustment
Prices quoted in currencies other than the national one are converted into the national currency using the average exchange rate for the reference month.
There are not seasonal adjustment.
Not applicable.
The objective of the Import Price Index is to measure the monthly evolution of the prices of those industrial products from the rest of the world.
1 April 2025
Aggregate index
Weighted arithmetic mean of elementary indices.
Basket of products
Set of products whose price is monthly collected.
Contribution
The contribution of a product is the extent to which the overall index changes when there are price changes only for that product (that is, all other prices remain constant).
Elementary index
Ratio of average prices in the current month to average prices in December of the previous year (multiplied by 100). Indices are unitless and measure price changes from the base period to the current month.
Import prices
Prices included in the index are producer prices with the following characteristics:
they are the prices existing at the national border, excluding VAT, other indirect taxes or customs duties, even though all sales or discounts are included. They are CIF prices (cost, insurance, freight), excluding transport or insurance costs relating to the part of the journey within Spain
they are current prices on 15th of the month
the currency is Euro. If the price is provided in a different currency, prices are exchanged to Euros.
Quality adjustment
Estimation of the price difference between the new (replacement) product and the old (replaced) one that is due to the quality change
Quality change
Change that occurs when the new product (variety or model) that replaces a previously selected one presents a change in its specifications that results in a significant difference in the utility of the product.
Rates of change
They show price developments between two periods of time.
Subvariety
Specific model of a product, in a concrete industrial establishment, whose price is collected monthly.
Weights:
Product weight is the relative importance of each product in the basket. Weights are calculated using the turnover from imports coming from Intrastat and the Single Administrative Document (SAD).
Local units which import industrial products in Spain. The observation units are the same as the information units.
The target population is all local units which import industrial products in Spain.
The frame is the Custom Data.
The whole national territory is covered except the Autonomous Cities of Ceuta and Melilla.
A breakdown by market is calculated, distinguishing between the Euro and the non-euro zone. The list of euro-zone countries is updated every time a new country joins the euro-zone.
The reference period for data is the month, in particular day 15th.
The accuracy is tackled at national and market (euro and non-euro zone) levels by eliminating non-sampling errors as much as possible and studying and analyzing revisions.
The main sources of error are non-response and overcoverage. There is no evidence that the response rate is distributed in a way that generates a bias in the index or its evolution. In addition, steps are taken to improve the updating of the sample, replacing, in a more agile way, units that have been deleted from the sample for new ones.
Due to the timeliness of the survey there is a non-response rate of 10%, at the time of the initial release. The questionnaires keep being required three months after the end of the reference month. This way new questionnaires are recorded after the first publication of the results and the non-response rate decreases. Another consequence is that the published results are updated monthly including both new and edited data.
Since the cut-off sampling is used, best sampling method to be used taking into account the skewness of the distribution of the Industrial businesses size in Spain, the estimation is biased, although there is no information about how much.
Data editing consists on several phases throughout the process. The first one is microediting and takes place during the data collection. The e-questionnaire contains workflows and several hard and soft edits. It makes possible that the data are cleaned by the respondent and there is no need to recontact. Finally the macroediting phase occurs, for the purpose of checking the results to be published.
During the whole data collection process the response rate is checked and attention is paid to get the data of the influential units.
Indices
Indices are compiled as ratios of prices in a given month to prices in the reference month (December of the previous year) multiplied by 100. Therefore indices are unitless.
Rates of change
All rates of change are usually given as percentage changes.
Weights
For each item or group of items, weights represent the corresponding percentage share of the total value of imports.
Data checking
As a general rule, respondents are recontacted in order to justify or correct any anomaly detected in the subvarieties or their prices during the validation process, in case they have changed the characteristics (both physical and commercial) or the unit of measure of the subvariety.
Index Calculation
First, the elementary indices are calculated as a ratio of the geometric mean of the prices collected in the month between the prices reported in December last year.
Subsequently, the elementary indices are aggregated using a weighted arithmetic mean.
Weights
The main source for the weights of the Import Price Indices of Industrial Products is Intrastat data and the SAD .
There are weights for each product in each market (Euro zone - rest of the world).
Treatment of missing items
When occasionally the product price has not been reported, the establishment is contacted to see if they can estimate the price that the transaction would have had.
If this is not possible, the price is estimated using the average change of the rest of prices collected for the same product or the corresponding branch in the same market.
Treatment of replacement products
When a subvariety disappears, INE contacts the informant to know if it is something temporary or permanent. In the event that the disappearance is permanent, the subvariety is to be replaced by another item of the same product.
In case the establishment does not have a substitute for the product, we try to find another establishment to provide information.
Adjustments for quality change
When there is a change in the specifications of a subvariety or it disappears and it is replaced, a quality adjustment must be done in order to determine the share of the price difference that is due to a quality change.
In general terms, estimated prices are used to make this adjustment. This method involves the estimation of a relative price change as the average price change of the aggregate that contains the subvariety (product or class).
The data used to calculate the Import Price Indices of industrial products are obtained by surveys of establishments. The frame of the survey is all establishments that have imported industrial products. The frame of the survey is the State Tax Office Foreign Trade database.
The criteria used to define which activities are part of the calculation of Import Price Index, base 2021, are: for the entire country, classes (4 digits NACE Rev. 2) that exceed 0.1% of the total turnover of the industry, and for the markets (Euro zone and non-euro zone), divisions (2 digits CNAE 2009) which exceed 1.0% of the total turnover of the industry in each market (according to the data of Customs in 2021).
In the Import Price Indices of industrial products, base 2021, around 19,000 prices of 2,100 products in approximately 5,200 establishments are monthly collected.
Monthly.
As established in the Regulation, the deadline for the data transmission is 45 days after the end of the reference period.
This deadline is met, since the results are published one month and four days after the end of the reference period, unless there is a public holiday. In this case, the results are published the previous working day.
The comparability between EU countries is ensured by the EBS-Regulation (Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics, repealing 10 legal acts in the field of business statistics) and its General Implementing Act (Commission Implementing Regulation 2020/1197 laying down technical specifications and arrangements pursuant to Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics repealing 10 legal acts in the field of business statistic). They provide these statistics with homogeneity regarding the rest of European Union countries, which disseminate the same information on their respective industrial sectors.
The Import Price Indices of Industrial Products were published for the first time in January 2005. Since then there has been a change in the used classification and another one in the base year.
Since January 2009, the Statistical Classification of Economic Activities in the European Community, Rev. 2 (NACE-Rev. 2) is used. Indices are available since the beginning of the series with the new classification.
The change of base has led to changes of some of the methodological aspect of the survey, which have led to a break in the series that has been suitably treated to provide linked series from the first year of publication of the survey to the present date. Thus, the time series are comparable since their beginning in January 2005.
