Monthly producer price indices of industrial products

Statistical Office of the Republic of Serbia (SORS)

Price statistics department

5 Milana Rakica str., Belgrade 11000, Serbia

Producer price index of industrial products (PPI) are calculated:

• for domestic market (Indices of producers’ prices of industrial products for domestic market)
• for non-domestic market (Indices of export producers' prices)
• total for domestic and non-domestic market (Indices of producers’ prices of industrial products total)

The objective of the survey is to calculate, according to collected prices and respective weights, producer price indices of industrial products in domestic and international market. Indices are regarded as indicators of dynamics of producer prices of industrial products.

NACE Rev. 2

Sections B to D and Division E36

Selling producer prices of industrial products for domestic market are the prices at which producers sell their products to buyers in domestic market in major quantities FCO loaded (wagon/truck) in the place of producer. In other words, producers apply these prices for calculations with other producers or in trade, in cases of joint ventures. The prices include subsidies, if granted to producer, and deducted are commercial rebate and discount (cash discount, etc.) that sellers grant to buyers. Selling producer prices of industrial products for exports are the prices of goods delivered at national border, including costs of transport, insurance, and all other costs incurred before the border point (FOB price), which affect unit price of products. These prices does not include value added tax and discounts that seller may grant to buyer.

According to the above stated definitions, selling producer prices of industrial products present actual and not average prices of products. Average prices calculated for reporting period are not acceptable, regardless the fact the product of the same quality was sold at various prices, or the sales terms remained unchanged. Therefore, selling producer price of industrial products presents the actual amount of money that producer receives from buyer, for a measurement unit of precisely defined quantity (type) of product, achieved in domestic or international market.

Observation unit are enterprise and their products. Reporting unit is enterprise.

Producer prices of industrial products are followed for over 2400 products, classified into sections B, C, D and E, 29 divisions, from about 600 industrial producers on the territory of the Republic of Serbia

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).    

The producer price indexes on domestic market are calculated from 1966.

The producer price indexes on non-domestic market and Total PPI are calculated from 2008.

Base (reference) year: 2015

Indices.

Month

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

PPIs data are available to the users on the SORS website.

PPIs data are transmitted to Eurostat through eDAMIS.

Data confidentiality is stipulated by:

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

(www.stat.gov.rs/media/2322/zakon_o_statisticie.pdf)

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

(www.stat.gov.rs/media/2343/rulebook-on-statistical-data-protection-in-sors.doc ) 

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

(www.stat.gov.rs/media/2341/guidelines-on-measures-of-data-and-information-protection-in-the-sors.doc )

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).

Calendar of releases is available at SORS website:

http://www.stat.gov.rs/en-US/calendar

The data obtained through statistical surveys are released at the internet presentation (http://www.stat.gov.rs/en-US/),

in the database (http://data.stat.gov.rs/?caller=SDDB&languageCode=en-US),

Monthly.

Statistical release PPI for domestic market is published at the same time with statistical release PPI for non-domestic market on the SORS website, at 12:00 (local time), in Serbian as well as in English language. Statistical release for Total PPI is published two days later in the same local time.

SORS  complex publications:

• Monthly statistical bulletin.
• Statistical pocketbook of Serbia.
• Statistical Yearbook of the Republic of Serbia.

PPI’s data are posted on the SORS website: http://www.stat.gov.rs/en-US/publikacije

Current data are sent monthly to Eurostat via eDamis.

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

http://www.stat.gov.rs/en-US/istrazivanja/methodology-and-documents/

Not applicable.

There is no specific process to focus on quality.

Not applicable.

PPI’s data primarily are used as follows:

•  economic indicators essential in creating fiscal and monetary strategy (National Bank, Ministries and other representatives of  government),
• deflators of time series, especially for the needs of national accounts and industry, 
• tools for price harmonization when conducting various sales and purchase agreements.

No information.

PPI’s are covering sections B to D and Division E36 according NACE Rev. 2.

The products for price monitoring are selected from each industrial division, with the highest sale on the domestic and international 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.

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.

Response rate is 70%. 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 asking the enterprise to estimate the missing price or repeating the last reported price. In cases when an industrial enterprise cease to manufacture a product of the quality for which the prices were offered, or if a product of the subject quality is “non-marketable goods”, then a new quality shall be defined for the product that is best sold and that is anticipated to be sold for 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.

The reporting period extends from the 16^th day previous month to the 15^th day of the current month. Industrial enterprises complete forms between the 15^th and the 16^th day every month with the prices for the period and forward them to the Statistical Office of the Republic of Serbia until the 28^th day of the subject month. 

PPI`s for domestic and non-domestic market are published each month about 5<sup>th</sup> and relate to the previous month in the edition Statistical Release with the mark CN 20 and CN 21, Total PPI is published each month about 7<sup>th</sup> with the mark CN 22  and they are presented on the website of the Statistical Office of the Republic of Serbia (www.stat.gov.rs). 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 about 23<sup>nd</sup> and 25<sup>nd</sup> February. First data for PPI`s are also final data, and are not corrected at a later stage.

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

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

Comparable time series are available

- PPI for domestic market from the January of 2005.

- PPI for non-domestic market from the January of 2008.

- Total PPI from the January of 2008.

There is no other statistical output for comparison.

PPI on domestic and PPI on non-domestic market are consistent and coherent with Total PPI as Total PPI is calculated from PPI’s data on domestic and non-domestic market.

No information.

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. 

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

Product/Item selection:

Since the methodology of price statistics is based on the principle of representation, producer prices of industrial products are followed for a certain number of production units, being reporting units at the same time. Primarily selected are enterprises featuring large production and output 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 production output. 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 output and turnover or those discontinued shall be replaced with other products of the same class that have the largest output, i.e. turnover.

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 turnover 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 output, and they are calculated according to the data on total output from the Annual structural business survey (SBS-01). For producer prices of industrial products in domestic market, weight of a division is calculated by subtracting the value of exports of the division from the respective output value from the Annual structural business survey. For producer prices of industrial products in foreign market, as weight of a division anticipated is the respective value of annual exports of the division. 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 the Annual survey of industry on production output in domestic market (IND-21) and the data of external trade statistics on annual value of exports according to the CA, for the products exported. The output coverage within certain division is full, regardless the number of the selected products within the division. The output value of the non-covered products is added to the output value of the selected products and therefore the sum of values the selected products within a division represents the actual output 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.  

Monthly.

The data on producer (sales) prices of industrial products are provided by enterprises using C41 questionnaire for domestic market and C41I questionnaire for foreign market. The reporting period extends from the 16^th day previous month to the 15^th day of the current month. Industrial enterprises complete forms between the 15^th and the 16^th day every month with the prices for the period and forward them to the respective statistical authorities until the 28^th day of the subject month. 

In cases when there were no sales in a reporting period, industrial enterprises enter the prices that would have been applied if the purchaser had appeared. Therefore, C41 form shall be filled with the price for a selected product provided the product is in the production range of the industrial enterprise. If there were no sales in foreign market in a reporting period, the form C41I shall be forwarded with a note that no exports were made in this 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.

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.

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 asking the enterprise to estimate the missing price or repeating the last reported price. Correction of prices in case of quality changes is also done if necessary.

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). Product 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 product 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 producer prices of industrial products:

where:

P_n      = product price in current month,

P₀      = product price in base period,

W₀     = value of sold quantities in base period.

iod.

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.

NA