National Statistical Institute

National Non-financial Accounts

Hadil Shehebar

Nachko Milenov

Chief expert

2 P. Volov Str., Sofia 1038

[email protected]

[email protected]

+359 2 9857 537

+359 2 9857 670

Seasonally adjusted data are data that are removed periodically recurring within a one period component of the time series - seasonal and calendar variations. Seasonally adjusted data show highlights the behavior of the studied fluctuations (changes in the direction of development and changes related to the business cycle).

Classification of Economic Activities (CEA-2008, for international use NACE.BG-2008)

Total of economy.

Fluctuations caused by abnormal levels of seasonal factors (e.g., extreme weather conditions or unusual circumstances) are visible in the seasonally adjusted data because they exceed or fall below the average seasonal values. Deviations of an occasional nature and unusual changes for which there is an economic explanation (e.g., effects of changes in economic policy, large procurement, natural disasters, etc.) are not eliminated in the season adjustment, i.e. they are part of the seasonally adjusted data.

Seasonal adjustment also includes the elimination of calendar effects, as far as they result from the difference in the number of weekdays and weekends, and can be quantified.

Seasonally adjusted data are data that are removed periodically repeated within period components of the series - seasonal and calendar variations. So seasonally adjusted data highlights the behavior of the studied variables (changes in the direction of development and changes related to the business cycle).

The seasonally adjusted lines contain random component (noise) having different levels in different series and the amount depends on the economic nature of the study, and applying the method of seasonal adjustment .

Seasonal adjustment of statistical indicators in the NIS is organized according to the "Guide of the European statistical system for seasonal adjustment". The procedure is performed using the software developed by Eurostat product Demeter, where by the algorithm TRAMO / SEATS.

The procedure for obtaining seasonally adjusted data includes correction of the series in terms of calendar effects and abnormal values. Calendar effects are expressed as :

• differences in the number of working days in a given period;
• effect of leap years ;
• holidays with variable dates (Easter).

Adjustments for differences in the number of working days are made to obtain seasonally adjusted data, which are independent of the number and structure of days (number of Mondays, Tuesdays etc. / number of weekdays and weekends) in the quarter.

Abnormal values (outliers) are unusual changes in time series of a given indicator. Their manifestation can be in several ways, the most significant are the peak values (abnormal values of individual observations in the order), short-term changes (series of abnormal values to change the level of the indicator for a short period of time), changes in the level (a series of abnormal values ??with constant size and time- effect on the level of the indicator).

Institutional unit under ESA2010 - enterprise, household, public institution.

economic territory of the country

Bulgaria

from 1995 (Infostat)

2015

Information sources are not adjusted quarterly data for these indicators.

Quarterly

Quarterly data

Apply seasonal adjustment of the data using software JDemetra+.

· European Statistics Code of Practice;

· Common framework for quality management in the National Statistical System.

Questionnaire on the implementation of the principles of the European Statistics Code of Practice.

About the methods and revisions of seasonally adjusted data, seasonal adjustment of statistical indicators in the NIS is conducted in a harmonized European methodology described in the "Guide of the European statistical system for seasonal adjustment." The procedure is performed using the software developed by Eurostat product Demetra, whereby applied the algorithm TRAMO / SEATS.

Of seasonal adjustment are subjected data on GDP components. Applies direct method of seasonal adjustment, in which the aggregates and their components undergo self - smoothing. As a result, there is a non - additivity of the seasonally adjusted data - the aggregates are not equal to the sum of their components. The parameters of the model for seasonal adjustment are determined after the calculation of the final data for a given year (October each year) and in case of a change in the used classification of economic activities. This targeted model is used to revise the seasonally adjusted values for the quarters within the whole time series.

Quarterly rates:

• Flash estimates of GDP - T +42-43 days after the reporting period
• Current quarterly estimates of GDP - T +65 days after the reporting period

Additional information on other indicators in national accounts are available in other subject areas related to national accounts.

Press Release

Data are available to all users of the NSI website under the heading Macroeconomic statistics - Gross Domestic Product - Quarterly seasonally adjusted data: http://www.nsi.bg/en/node/12590

Not applicable.

Guide to the European Statistical System for seasonal adjustment, European System of Accounts (2010) (Eurostat).

· Law on Statistics;

· 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 with du account for technical developments and the requirements of users in a democratic society.