Calculation of producers’ price index of industrial products from imports

Period: Annual
Year: 2022

01. Contact
02. Metadata update
03. Statistical presentation
04. Unit of measure
05. Reference Period
06. Institutional Mandate
07. Confidentiality
08. Release policy
09. Frequency of dissemination
10. Accessibility and clarity
11. Quality management
12. Relevance
13. Accuracy and reliability
14. Timeliness and punctuality
15. Coherence and comparability
16. Cost and Burden
17. Data revision
18. Statistical processing
19. Comment

SDMX Download

01. ContactTop
01.1. Contact organisation

Statistical Office of the Republic of Serbia

01.2. Contact organisation unit

Price statistics department

01.3. Contact name

Ana Zivkovic

01.4. Contact person function

Statistician analyst

01.5. Contact mail address

5 Milana Rakića, Belgrade

01.6. Contact email address

01.7. Contact phone number

+381 11 2412922, ext. 231

02. Metadata updateTop
02.1. Metadata last certified
02.2. Metadata last posted
02.3. Metadata last update

03. Statistical presentationTop
03.1. Data description

The subject of this research is import prices of  producers of industrial products.

The objective of the survey is to calculate, according to collected prices and respective weights, producer price indices of industrial products from imports. Indices are regarded as indicators of dynamics of import prices of producers of industrial products.

03.2. Classification system

NACE Rev. 2

03.3. Coverage - sector

Sections B to C 29 except: 05, 07, 09 and 18.

Enterprises with an annual turnover below 1.5 million EUR are not included in the reference population.

03.4. Statistical concepts and definitions

Import prices are actual transaction prices (c.i.f.) for products which importers buy in largest quantities, excluding all duties and taxes, as far as possible on the 15th in the month.

03.5. Statistical unit

Observation units are industrial and trading enterprises and their products. Reporting unit is enterprise.

03.6. Statistical population

Import prices are followed for over 280 products, classified into sections B and C, 22 divisions, from about 120 enterprises on the territory of the Republic of Serbia.

03.7. Reference area

Republic of Serbia. Starting from 1999 the Statistical Office of the Republic of Serbia has not at disposal and may not provide available certain data relative to Kosovo and Metohia and therefore these data are not included in the coverage for the Republic of Serbia (total). 


03.8. Coverage - Time

Import price indexes are calculated from 2017.

03.9. Base period

Base (reference) year: previous year.

04. Unit of measureTop
04. Unit of measure


05. Reference PeriodTop
05. Reference Period


06. Institutional MandateTop
06.1. Institutional Mandate - legal acts and other agreements

National legislation:

- Official Statistics Law
- Resolution on the Programme of official statistics
- Regulation on the Plan of official statistics for the current year
* The above documents are available at SORS website:


06.2. Institutional Mandate - data sharing

SORS is the only institution in the country engaged in the production of the IMPI.

IMPI`s data are available to the users on the SORS website.

IMPI`s data are transmitted to Eurostat through eDAMIS.

07. Confidentiality Top
07.1. Confidentiality - policy

Data confidentiality is stipulated by:


- Official Statistics Law (Official Gazette of RS, number 104/2009), Articles 44, 45, 46, 47, 48, and 49.


- Rulebook on statistical data protection in the Statistical Office of the Republic of Serbia


- Guidelines on measures of data and information protection in the Statistical Office of the Republic of Serbia

( )


07.2. Confidentiality - data treatment

In order to protect individual's information privacy and business interests of business units, only aggregated data are published (observation units are not recognizable either directly or indirectly). Therefore, adjusted contents of the tables are in use and certain rules are applied to protect data, such as a threshold minimum number of units (Official Statistics Law (Official gazette RS, no 104/09).

08. Release policyTop
08.1. Release calendar

Calendar of releases is available at SORS website on the 1st day of December every year for the forthcoming year (


All SORS releases are launched at 12.00.
Any divergence from the defined time schedule are announced in advance and explained in the Calendar.  


08.2. Release calendar access

Calendar of releases is available at SORS website:


08.3. Release policy - user access

The data obtained through statistical surveys are released at the internet presentation (,


in statistical releases and publications ( 
The results of official statistics are available at the same time to all users on impartial basis; any privileged access by external users before their release is not allowed.  


09. Frequency of disseminationTop
09. Frequency of dissemination


10. Accessibility and clarityTop
10.1. Dissemination format - News release

Statistical release IMPI is published on the SORS website, at 12:00 (local time), 10 days after the end of the reference month, in Serbian as well as in English language.

10.2. Dissemination format - Publications

SORS  complex publications:

  • Monthly statistical bulletin.
  • Statistical pocketbook of Serbia.
  • Statistical Yearbook of the Republic of Serbia.
10.3. Dissemination format - online database

IMPI`s data are posted on the SORS website:

10.4. Dissemination format - microdata access

On request, the access to anonymized microdata is ensured to scientific and research institutions.


The request can be placed by email at, or by regular mail addressed at 
5 Milana Rakića St, Belgrade.


10.5. Dissemination format - other

Current data are sent monthly to Eurostat via eDamis.

10.6. Documentation on methodology

Detailed methodological explanations are available on the website of the Statistical Office of the Republic of Serbia:

10.7. Quality management - documentation

Not applicable.

11. Quality managementTop
11.1. Quality assurance
The SORS quality management system is relied on the Serbian official statistics mission and vision, as well as on the European Statistics Code of Practice – CoP and the Total Quality Management – TQM principles, which together make the common quality framework of the European Statistical System (ESS).


For more information, please see the documents at


11.2. Quality management - assessment

Not applicable.

12. Relevance Top
12.1. User needs

IMPI`s data primarily are used as follows:

•        economic indicators (National Bank, Ministries and other representatives of  government),

•        deflators of time series, especially for the needs of national accounts.

•        tools for price harmonization when conducting various sales and purchase agreements.

12.2. User satisfaction

On biennial basis (once in two years), by the means of web interview, implemented is the User Satisfaction Survey. The survey results are available at SORS website:


12.3. Completeness

IMPI`s are covering sections B to C 29 according NACE Rev. 2.

13. Accuracy and reliabilityTop
13.1. Overall accuracy

The products for price monitoring are selected from each industrial division, with the highest imports on the domestic market and their prices can represent the general price trends in the industry by division and according to products destination (MIGs). When creating the list, the selected products should represent the fluctuations of prices also for the products not included in the list.

13.2. Sampling error

Sampling error cannot be calculated because the methodology of price statistics based on the principle of representativeness. Primarily are selected enterprise by greatest production and realization of selected products.

13.3. Non-sampling error

Response rate is over 90%. Enterprises in terms of their size or representativeness are contacted by phone in order to have the data on time. Price for temporarily missing product is processed by repeating the last reported price. In cases when an enterprise cease to import a product of the quality for which the prices were reported then a new quality shall be defined for the product with the largest import and that is anticipated to be imported for a long time and in large quantities. For the new selected quality of a product, the prices are given simultaneously for the current and the previous month, and in reports stated are always the prices for the same quality of a product. Enterprises shall be obliged to explain any quality change.

14. Timeliness and punctualityTop
14.1. Timeliness

The reporting period is the month. Enterprises complete reports with the prices as far as possible on the 15th in referent month and forward them to the respective statistical authorities until the 28th day of the subject month.

IMPI`s are published each month about 10th and relate to the previous month in the edition Statistical Release with the mark CN23 and they are presented on the website of the Statistical Office of the Republic of Serbia ( An exception is only the month January when, due transit to a new year and the methodology changes in indices related to that, data are published  28nd February. First data for IMPI`s are also final data, and are not corrected at a later stage.

14.2. Punctuality

Statistical releases for IMPI`s are published each month according to the announced release calendar.

15. Coherence and comparabilityTop
15.1. Comparability - geographical

IMPI`s are calculated for the whole country and the representativeness and the comparability of the indicators across countries is good.

15.2. Comparability - over time

IMPI`s are calculated from the January of 2017.

15.3. Coherence - cross domain

There is no other statistical output for comparison. In import price statistics we use data from foreign trade statistics for designe sample frame and for calculating weights.

15.4. Coherence - internal

Aggregates at higher level are consistent with their sub-aggregates on lower level.

16. Cost and BurdenTop
16. Cost and Burden

Not applicable.

17. Data revisionTop
17.1. Data revision - policy
The SORS general revision policy constitutes the global frame ensuring that each statistical domain shall define its own revision policy in compliance with its specific nature. 


The general SORS revision policy determines:
- general rules of revisions of the published data,
- forms of informing users as regards the possible causes of revisions,
- categories of revisions, and
- documents covering all aspects of revisions.
The general SORS revision policy is available at


17.2. Data revision - practice

Major changes in methodology are announced in advance or at the time of data dissemination.

18. Statistical processingTop
18.1. Source data

Product/Item selection:

Since the methodology of price statistics is based on the principle of representation, import prices in industry are followed for a certain number of import units, being reporting units at the same time. Primarily selected are enterprises featuring large import volume of respective products.

For each industry division created is a separate list of products, the prices of which shall be followed. The products of a division are classified into a number of groups, classes and subclasses, and for them reliable data on fluctuations of prices shall be provided. When creating the list, the selected products should represent the fluctuations of prices also for the products not included in the list. Therefore, important is the contents of every group, class and subclass of products. Included are the products with the largest share in the overall import. The number of representative items in classes and subclasses depends upon classes’ homogeneity. As a rule, homogenous classes require a smaller number of representative items than less homogenous ones, since the price variations in homogenous classes are smaller. Each selected product shall be specified as much as possible and this shall ensure the comparability of prices of the products of the same quality. The products with decreased import or those discontinued shall be replaced with other products of the same class that have the largest import.

Every year the list of products shall be analyzed and updated when required. Larger changes, i.e. the revision of the list of products are carried out every fifth year, when the weights are also changed.

Sources of weights:

The purpose of index weighting is that each product is represented according to its share in total import and thereby group/class index shall be representative as a synthetic indicator of complex phenomena. The weights used for group/class indices of producer prices of industrial products are calculated according to the data of regular statistical surveys. Firstly the weights for all divisions are calculated, and then the weights for each product within a division. Weights of divisions actually represent the share of any industrial division in the total value of annual import. Weights of sections and subsections are obtained as the sum of the weights of the respective industrial divisions.

Weights for products within a division are calculated according to the data of external trade statistics on annual value of imports according to the CA, for the products imported. The import coverage within certain division is full, regardless the number of the selected products within the division. The import value of the non-covered products is added to the import value of the selected products and therefore the sum of values the selected products within a division represents the actual import of the division. In this way, the weighting system fully complies with the representation principles.

Weights are changed (calculated) every fifth year and this is in accordance with international recommendations and practice. The current weights have been applied since 2017 and they were calculated according to the data for 2015. 

18.2. Frequency of data collection


18.3. Data collection

The data on import prices in industry are provided by enterprises using C41U questionnaire. Enterprises complete reports with the prices as far as possible on the 15th in referent month and forward them to the respective statistical authorities until the 28th day of the subject month.

All data collection is done by postal questionnaires (sending for each month separately). Data collection via Internet (Web questionnaires) is planed in the nearest future.

18.4. Data validation

The staff of the Price Statistics Division performs checking of prices on questionnaires and control of data entry by comparing calculated monthly indices between the current and the previous month and clarifies all significant changes with reporting units via the telephone and e-mail.

18.5. Data compilation

After the receipt of reports on prices (deadline: 28th day in a month), the data checkup and their entry are carried out. Price for temporarily missing product is processed by repeating the last reported price. Correction of prices in case of quality changes is also done if necessary.

Import price indices are calculated for certain products (individual indices), for groups/classes (group/class indices) and for all products included in the index list (total index). Import prices are used for the calculations of individual indices, while group/class indices are calculated by weighting individual indices. For the purpose of this survey, average import price for previous year is used as the base.


Aggregated (i.e. group/class) indices are calculated by weighting individual indices according to Laspeyres formula, which is applied in our price statistics for calculating the indices of import prices in industry:



Pn      = product price in current month,

P0      = product price in base period,

W0     = value of sold quantities in base period.

18.6. Adjustment

Prices quoted in other currencies are converted into the national currency using the exchange rate of the reference date (15th of each month).

No seasonal adjustments are made.

19. CommentTop
19. Comment