|Unit||Index 2015=100, NSA|
|Adjustments||Not Seasonally Adjusted|
Producer price index in industry (PPI)
The producer price index in industry (PPI) is an indicator describing changes in producer prices over a defined period of time. Its calculation is based on the monitoring of these prices for certain item representatives in specially selected enterprises. The base or comparison period of PPI is the year 2005 (2005 = 100).
The PPI has been calculated since 1991. In 2001 the calculation of PPI was started separately for the products sold on the domestic market and for the products, which the industrial enterprises export.
Producer price indices are used for the calculation of the index of the physical volume of industrial products at constant prices and for the estimation of the gross domestic product at constant prices as well as for economic analysis and international comparisons.
Producer price changes
Producer price changes over the corresponding period of the previous year reflect price changes within a twelve month. The annual average producer price changes show the average price changes in the 12 months of the reference year in comparison with the corresponding 12 months of the previous year. Price changes over the previous month reflect changes in the average price level during a month.
Source of data
Sample survey of producer prices.
Information on producer prices is obtained by recording prices for defined item representatives of goods in specially selected enterprises. Enterprises with as large as possible share of product sales in the respective industrial activity (NACE class) are selected. Target sampling is made from the general population consisting of enterprises, business companies with central and local capital participation and business companies of other ownership forms with the number of employees 20 or more, or with net turnover in the preceding year exceeding 300 thousand lats.
In 2010, the sample of producer prices included more than 580 enterprises. Their share in the total industrial sales volume in 2008 was higher than 80%. Price recording covers 153 NACE Rev. 2 classes. (industrial activity in the country is covered by 171 classes). 2.1 thsd prices were surveyed, of these, 1.3 thsd were recorded for products sold on the domestic market and 0.8 thsd for exported products. The list of enterprises involved in price recording is reviewed every year and small enterprises with unstable production operations are excluded while enterprises playing a significant role in the respective industrial activity are included. The list of item representatives of goods is also updated regularly. During the meetings with the experts of the sampled enterprises the statisticians select specified item representatives for further registration of producer prices.
Description of data
Prices are recorded on a monthly basis. The respondents show the current producer price (excluding VAT and excise tax) for which a representative of goods – a specific product – was sold on the 15th day of the month. If there were no sales transactions on this day, a date closest to it is indicated. If a homogeneous group of goods was selected as an item representative, the average monthly prices are collected.
Methods of calculation
PPI is calculated by applying a Laspeyres-type formula, which compares the value of the “basket” of item representatives in the reference period with its value in the base period. The prices of December of the previous year serve as a base for price comparisons. The amount of products sold two years ago in breakdown by NACE sections, divisions, groups, and classes is used as weights. In order to ensure the symmetry of weight and price base periods, the weights applied to the calculation of PPI for 2010 have been recalculated into the prices of December 2009.
Statistical Classification of Economic Activities in the European Communities NACE Rev. 2 was introduced in PPI calculations starting with January 2009.
Until the end of 2008 previous version of classification (NACE Rev. 1.1) was applied in calculations. In order to ensure comparability of price indices in industry, which were calculated according to different classifications, retrospective data on 2001 – 2008 are recalculated according to classification NACE Rev. 2.
PPI is calculated according to chapters, sections, groups, and classes, as well as to 5 production basic groupings of NACE Rev. 2 (intermediate consumption goods, means of production, consumer durables, consumer non-durables, energy).
In some cases, due to specifics of electronic data processing technologies and rounding adjustments, slight discrepancies may occur between the published data and calculations made by the data users.
If a respondent has made an error and given wrong prices but in the next month’s survey adjusts the data for the previous month, producer price indices for that month are not recalculated.