National Statistical Institute

Statistics on Living Conditions Department

Petia Manahova

State Expert

2, P. Volov Str.; 1038 Sofia, Bulgaria

[email protected]

+359 2 9857 612

The variable Purchasing power of the households is estimated based on the information from HBS. The purchasing power is the quantity of a given kind of good, which can be bought with the annual monetary or total income of the household if it is used to buy only this kind of good. Data are represented as absolute values.

· Classification of Individual Consumption by Purpose (COICOP). From 2026 a new version of Classification of Individual Consumption by Purpose – COICOP 2018 is used;

· International Standard Classification of Education (ISCED 2011);

· National Classification of Occupations and Duties-2011 (NCOD-2011);

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

· Classification of territorial units for statistical purposes in Bulgaria (NUTS).

The Household Budget Survey is a sample survey by implementation of two stage cluster. The general population from which the sample for the survey is formed comprises all the households in the country.

Institutional households are not studied by the household budget survey.

The unit of observation is every randomly chosen ordinary household irrespective of the number of members and their material and personal status.

The sample size for the 2010 - 2025 period is 3060 households and since 2026 - 5580 households each quarter.

The variable Purchasing power of the households is estimated based on the information from HBS. The Purchased power represents the volume of a given kind of goods, that could be bought with the annual monetary or total income of the household, in case only used to buy this kind of good. The data are presented as absolute values.

The variable Index of Purchasing Power represents the changes of the purchasing power in relation to a base year.

Household (ordinary household).

The general population from which the sample is formed comprises all ordinary households in the country.

Institutional households are not studied by the HBS.

According to the Classification of territorial units for statistical purposes in Bulgaria (NUTS).

Since 2004 to 2025 - yearly data.

Not applicable

BGN (up to 2025), EUR, per cent (%), kg, litre, number, number of persons.

Year

· Regulation (EU) 2019/1700 of the European Parliament and the Council of 10 October 2019 establishing a common framework for European statistics relating to persons and households, based on the data at individual level collected from samples;

· Commission Implementing Regulation (EU) 2022/2094 of 28 October 2022 specifying the technical items of data sets, establishing the technical formats for transmission of information and specifying the detailed arrangements and content of the quality reports on the organisation of a sample survey in the consumption domain.

Not applicable.

· Law on Statistics;

· Regulation (EC) No 223/2009 on European statistics;

· Regulation (EU) 2016/679 on the protection of natural persons with regard to the processing of personal data and on the free movement of such data;

· Law on personal data protection. 

Individual data are not published in accordance with article 25 of the Law on Statistics. The publishing of individual data can be performed only in accordance with article 26 of the same law and Rules for provision of anonymised individual data for scientific and research purposes.

In April of the year following the reference year.

The calendar is available on the NSI website: https://www.nsi.bg/en/calendar

The data are published on NSI website, section Household Income, Expenditure and Consumption and in the INFOSTAT Information system in accordance with the Law on Statistics (Chapter 5) and the European Statistics Code of Practice, respecting professional independence and in an objective, professional and transparent manner in which all users are treated equitably.

Yearly

News release for publication „Average prices and purchased quantities of main foods and non-foods by households“.

· Publication "Average prices and purchased quantities of main foods and non-foods by households" (up to 2024) - contains data on the average prices and purchased quantities foods and non-foods by households by years and by quarters. The information from the survey of household budgets is used and because of that these average prices differ from the consumer prices published by the NSI. The purchased quantities foods are computed average per household and the purchased non-foods - average per 100 households. Published are also data on the purchasing power of households calculated by means of total and monetary income, as well as the changes in the purchasing power.

· General Publications of the NSI.

Detailed results are available to all users of the NSI website under the heading Households Income, Expenditure and Consumption: https://www.nsi.bg/en/statistical-data/246

and in the INFOSTAT Information system: https://www.nsi.bg/en/infostat.

Not applicable.

Information service on request, according to the Rules for the dissemination of statistical products and services in NSI.

· Methodology and organisation of the household budgets survey:

http://www.nsi.bg/sites/default/files/files/metadata/HH_HBS_Metodology_en.pdf

· Instruction for interviewers of Household budget survey.

Not applicable.

Through checking on field work and control of the thoroughness of the records in the diaries.

Not applicable.

The data of the average prices and purchased quantities goods is of interest to a wide number of users - state authorities, public and international organizations (Eurostat, OUN, ILO, etc), students and others.

No user' satisfaction surveys are carried out.

Not applicable.

As with any other sample survey, HBS may be burdened with errors due to sampling and other relating to the inability to be interviewed some of the units in the sample, as well as the errors taking place at the stage of data recording, data processing, etc. 

The errors calculated for the main indicators are published in the Quality Report on the NSI website under the heading Households Income, Expenditure and Consumption.

Like any statistical survey and household budget survey may contain non-sampling errors that arise at different stages of the study and which cannot be completely eliminated.

Such errors are basically:

• coverage errors;
• measurement errors that occur at the time of data collection;
• processing errors;
• non-response errors.

In order to reduce non-sampling errors:

• Update of the household lists for each of the first stage selection census enumeration areas;

• Development of a clear research methodology, ongoing updating of data coding systems;

• Using interviewers with experience in collecting, controlling, encoding and inputting data;

• Conducting regular training seminars for the interviewers;

• Assistance to the interviewers of the survey team at NSI;

• Data control at the collection, input, and processing stage.

Annual data are published in April of the year following the reference year.

The deadlines announced in the Calendar for the dissemination of the results of the NSI statistical surveys are respected.

Not applicable.

Break in time series in 2026 due to methodological changes and new Classification of Individual Consumption by Purpose (COICOP).

Household budget survey is consistent with Consumer Price Index, Purchasing Power Parity and National Accounts. Additional analyzes are carried out to ensure consistency with the survey on income and living conditions.

Burden of the respondents – once of the quarter.

Not applicable.

Not applicable.

The general population from which the sample for the survey is formed comprises all the ordinary households in the country.

When forming the sample a two stage cluster’s sampling on a territorial principle is implemented as follows:

• at the first stage the clusters are selected (enumeration areas from the last Census);
• at the second stage the households to be surveyed are identified.

Up to 2009 the selection of territorial units is done with a probability proportional to their size. Since 2010 non-proportional selection has applied in order to produce more accurate sample data in the small regions.

In the selected enumeration areas (clusters) lists of the household are prepared and they are arranged into ascending order, depending on the number of persons. 6 households from these lists are chosen from each cluster with a selection step.

From 2010 to 2025 the sample size is 3 060 households divided in three subsamples each containing 1 020 households. From 2026 the samples includes  5 580 households, 1 860 households in each subsamples. Each subsample is surveyed one month per quarter by application of the method of rotation sample. Each household participates in the survey four months during the 12-month period.

The household budget survey applies the principle of the voluntary participation of households which had randomly come into the sample. Every randomly selected household which is not willing or is not able to cooperate is replaced with another from the same cluster and with the same number of members.

Main documents of the Household budget survey are:

• Household dairy;
• Household questionnaire;
• Individual questionnaire.

Monthly to 2009 and quarterly since 2010.

Derivative indicators are calculated on the bases of primary data from HBS.

Logical control of data is happened at the time when the information is introduced.

Data processing is done with specially developed software for the needs of the survey in the Department Statistical Survey of the Regional Statistical Offices of the NSI. Data processing is carried out at the NSI.

The processing includes several stages:

• input and control of the collected data for each household observed during the month;
• quarterly aggregation of the monthly data;
• applying methodologies for assessing individual household data for the two months during which they were not directly observed;
• applying methodologies for calculating additional result variables:

Ø  a household in kind expenditures by type of expenditure

Ø  an equivalent household size

• annual aggregation of quarterly data;
• applying methodologies to add retrospective data for the months when households are not directly observed;
• obtaining tables with annual estimates of the main indicators for the survey.

Not applicable.