NSI (National Statistical Institute)

Short-term Business Statistics and Transport Statistics Department

National Statistical Institute
2, P. Volov Str.; 1038 Sofia, Bulgaria.

Road freight data collection consists of three datasets with quarterly periodicity:
1. Vehicle related variables dataset for a sample of road good motor vehicles contain, among others, indication about the type and age of the vehicle, the economic activity of the owner of the vehicle, the total kilometres loaded or empty.
2. Journey related variables dataset which contain, among other indications about weight of goods, regions of loading and unloading, distance driven, and tonne-kilometres performed during a journey
3. Goods related variables dataset which contain among others the type of goods transported and their weight and distance travelled, regions of loading and unloading.

Statistics on carriage of goods by road apply the following statistical classifications:

• The type of goods transported by road was collected, until reference year 2007 (included), according to the 24 groups of goods following the "Standard Goods Classification for Transport Statistics/Revised (NST/R )".
• The regional coding is done in conformity with European legislation: "NUTS Nomenclature of territorial units for statistics" (see also NUTS). Economic activity class of the vehicle owner is an optional variable. Data were collected according to NACE Rev. 1 until the end of 2007. From the beginning of 2008 onwards, the economic activity has been classified according to NACE Rev. 2 (see  "Statistical Classification of Economic Activities in the European Community, Rev. 2 (NACE Rev. 2)").
• Type of dangerous goods is a mandatory variable, but it is reported only for those goods that fall into this category. The classification is based on "European Agreement concerning the International Carriage of Dangerous Goods by Road", Chapter 2.1, as published in Annex E of Council Regulation (EC) No 1172/98. Directive 2008/68/EC makes reference to ADR as regards the transport of dangerous goods by road.

The optional variable type of cargo follows the Classification of Cargo Types of UNECE (United Nations, Economic Commission for Europe - codes for types of cargo, packages and packaging materials, Recommendation 21 adopted by the Working Party on Facilitation of International Trade Procedures, Geneva, March 1986).

Data refer to road freight operation for own account or for hire or reward performed on national or international territory.

The main concepts used in Road freight statistics are the following, more details can be found in the Road freight transport methodology manual : 

A goods road motor vehicle is any single road transport vehicle (lorry), or combination of road vehicles, namely road train (lorry with trailer) or articulated vehicle (road tractor with semi-trailer), designed to carry goods
Cross-trade is international road transport between two different countries performed by a road motor vehicle registered in a third country.
National transport is Road transport between two places (a place of loading and a place of unloading) located in the same country by a vehicle registered in that country. 
International transport is Road transport between two places (a place of loading and a place of unloading) in two different countries and cabotage by road. It may involve transit through one or more additional country or countries.
Cross trade is International road transport between two different countries performed by a road motor vehicle registered in a third country.
Transit is any loaded or empty road motor vehicle, which enters and leaves a country at different points by whatever means of transport, provided the total journey within the country is by road and that there is no loading or unloading in the country.
Goods carried by road are any goods moved by goods vehicle
Place of loading/unloading of a goods road vehicle on another mode of transport

• Place of loading (of the goods road transport vehicle on another mode of transport): The place of loading is the first place where the goods road motor vehicle was loaded on to another mode of transport (usually a ship or a rail wagon).
• Place of unloading (of the goods road transport vehicle from another mode of transport): The place of unloading is the last place where the goods road motor vehicle was unloaded from another mode of transport (usually a ship or a rail wagon).

The reporting unit for road freight transport statistics is the goods road transport vehicle.

As the total number of statistical units (most commonly vehicles) is very large, sample surveys are carried out to collect information.  

The data provided are goods vehicles registered in Republic of Bulgaria.

Since first quarter of 2006

Not applicable.

Data are collected in tonnes, tonne-kilometres, vehicle-kilometres and in number of journeys (journey data) or in number of basic transport operations (BTO (goods related data)).

The road data are collected on a quarterly basis and are reported to Eurostat five months after the end of the reference period.

National level:

• The Law on Statistics of Bulgaria

European level: 

• REGULATION (EU) N° 70/2012   

National level :

 Data are published on the NSI official web site and in Information system INFOSTAT. Other national and international users can receive more detailed data, not published on the NSI web page upon request according to the NSI Regulation for dissemination of statistical products and services.

From Eurostat :

Eurostat submits annually semi-aggregated data (data exchange tables, see Commission Regulation (EU) No 202/2010 amending the Commission Regulation (EC) 6/2003) back to the reporting countries so that they can compile the total road freight transport on their national territories, including the operations by national hauliers and also those of all other reporting countries.

These data exchange tables include more detailed breakdowns than the publicly available tables. They also include, for each value, the information on the number of observations that the estimates are based on. In this way, the reporting countries can estimate the reliability of results that they aggregate from the data exchange tables.

National level:

• Law on Statistics

European level:

• 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 due account for technical developments and the requirements of users in a democratic society.

All road freight micro-data are treated as if they were confidential. Only aggregated data are published.

Data are published according to the deadlines set in the National statistical program and the Release calendar.

The calendar is available on the NSI website: http://www.nsi.bg/en/node/480

Data are published on the internet site of NSI and can be accessed from all users of statistical information.

Quarter, Annual

 Press release on transport

• Statistical Yearbook;
• Statistical Reference Book;

           „Bulgaria“ (brochure).

Data on Road freight transport are available to all users of the NSI website under the heading  http://www.nsi.bg/en/node/7167

The access to micro-data for research purposes is granted according to Commission Regulation (EC) No 831/2002 on access to confidential data for scientific purposes (addition of the 4 surveys:

European Health Interview Survey (EHIS), Community Statistics on Information Society (CSIS) - module 2: Households and individuals, Household Budget Survey (HBS), Carriage of Goods by Road (CGR)

Not applicable.

National characteristics of surveys, conducted in the reporting countries in 2017, were published in Methodologies used in surveys of road freight transport in Member States, EFTA and Candidate Countries. This latter publication also contains data on response rates, vehicle registers' quality, sampling rates and statistical errors in surveys carried out in 2016.

Methodologies used in surveys of road freight transport in member states and candidate countries.

• Usage of common definition and methods;
• Checks and validation of data at national level;
• Annual reports to Eurostat on the national characteristics of the data collection;

          Data validation from Eurostat according to checks set in the methodology manual

The survey is carried out according the international requirements.

Main users are state institutions, different organizations and specialized in the sector enterprises.

Not applicable.

In compliance with the rules (regulations).

Road freight data come from sample survey. The sample error should by up to 5%.

At the end of each reporting year the sample error in % is calculated. An error is calculated for each stratum separately in order to obtain the total error of the sample. This is done in respect of the tonnes and tonne-kilometres.

Underreporting can be considered as a prevalent bias of the road freight statistics. Having in mind that respondents ease their burden by omitting journeys, the underreporting is in principle an imminent systematic error.

The necessary actions are taken in order to reduce this error to minimum and to ensure better quality and completeness of the received data.

Data are normally updated once per quarter.

If new annual data (all four quarters of a calendar year) have become available, the annual datasets are also updated together with the quarterly datasets.

Road freight data are transmitted to Eurostat within 5 months after the end of the reference period, as specified in the Regulation (EU) 70//2012.

Not applicable.

The data are comparable over time since the year 2006.

The data on freight transport volume differ from the same data in other activities of transport statistics because the data have been collected with a sample survey and are therefore estimates.

The data are made internally coherent by using common methodology in data collections and the same rules of data aggregation.

Cost and Burden for the survey are defined according the National Statistical Program for each reference year.

Countries can update incomplete or revised datasets referring to previous quarters at the same time when they submit new quarterly datasets. Data are revised on the basis of detected errors.

Countries can update incomplete or revised datasets referring to previous quarters at the same time when they submit new quarterly datasets. Data are revised on the basis of detected errors.

Sampling register used for the survey

Name of register:

Register of Motor Vehicles

Name of organisation who maintains the register:

The Ministry of Interior

Frequency of update:

Quarterly updated

Frequency of access to draw the samples:

Once a quarter

Arrangements for accessing the register:

Bilateral inter-institutional agreement between the NSI and the Ministry of Interior for providing statistical information.

Information obtained from the register:

Vehicles’ registration number, type of vehicle, year of first registration, maximum permissible laden weight, load capacity, number of axes, region, name and address of the owner, model gross weight.

In the stratification of the sample are used region and gross weight.

Procedure for reminders:

First reminder: 2 weeks after the end of the surveyed week

Second reminder: 4 weeks after the end of the surveyed week

The response rate is adequate.

Weekly.

Sampling methodology

Statistical unit:

Tractive vehicle

Types of units excluded:

Vehicle with maximum permissible laden weight under 6 tonnes, military vehicles, vehicles of the Ministry of Interior and other public administrations, agriculture tractors and other motor vehicles not designed to carry goods, vehicles with weight and dimensions exceeding the normal permitted limits of the country.

Time unit:

1 week

 Reference year 2022

All (13 weeks)

Stratification:

The sample for each quarter of the year is stratified by vehicles’ gross weight (6 groups) and country’s regions (28 regions), which give 168 strata.

The annual size of the sample for 2014 is provided on the base of sample size, tonnes carried and tonne-kilometres performed in 2013 and is stratified by vehicles’ gross weight into 6 groups:

• Group 1: Lorries and special vehicles with gross weight up to 7 499 kg;
• Group 2: Lorries and special vehicles with gross weight from 7 500 kg up to 14 999 kg;
• Group 3: Lorries and special vehicles with gross weight from 15 000 kg up to 16 999 kg;
• Group 4: Lorries and special vehicles with gross weight from 17 000 kg up to 24 999 kg;
• Group 5: Lorries and special vehicles with gross weight above 25 000 kg;
• Group 6: Road tractors.

Each quarter the 6 groups sample is distributed proportionally by the 28 regions.

Recording of weight of goods:

Gross weight of goods is reported. The containers swap bodies or pallets are excluded from the weight of goods.

Recording of journey data sent to Eurostat:

Single stop: Respondents can record only one type of goods, i.e. goods of larger weight. If no type of goods is dominant, the commodity ‘Miscellaneous’ is recorded.

Multi stop: Each transport operation is recorded.

Collection deliver: For type 3 journeys with more than 5 points for loading and unloading, the respondents are asked to fill in the total distance travelled loaded and the total distance empty, the total weight of transported goods, the main type of goods and the number of stops.

Calculation of weighting factors:

N = number of vehicles in the register (in a stratum)

S = number of questionnaires used in analysis (in A1 dataset)

S’ = number of vehicles for which no activity was recorded, but vehicles could be considered as active (holiday, no work, etc.)

Optional variables covered:

• Vehicle empty kilometres
• Type of cargo
• Axle configuration
• Degree of loading of the vehicle

Additional variables collected compared to the legal requirements:

Environmental impact-related variables:

Type of fuel used and fuel consumption.

A1. Vehicle-related variables:

• possibility of using vehicles for combined transport (YES)
• axle configuration according to the nomenclature defined in the Regulation on road transport statistics (YES)
• vehicle operator’s NACE Rev. 2 at class level (four-digit level) (NO)

A2. Journey-related variables:

• place of loading, if any, of the road transport vehicle on another means of transport (YES)
• place of unloading, if any, of the road transport vehicle from another means of transport (YES)
• situation ‘fully loaded’ (procedure 2) or ‘not fully loaded’ (procedure 1) of the goods road transport vehicle during the journey in question, in terms of maximum volume of space used during the journey (procedure 0 = by convention for unladen journeys) (NO)

National level :

 Arithmetic and qualitative controls are used in the validation process.

From Eurostat :

Since 1999, micro-data from the reporting countries have to be submitted according to Commission Regulation 2163/2001. The data are then checked and validated by EUROSTAT (verification of many different codes used (NUTS 3, numeric or alphabetic variables) correctness of linked questionnaires in the different dataset, etc ). Detected errors are then reported back to the data sender with the request for correction, this is an iterative process until at least 99.5% of all data records are validated and loaded in the database.

IS RFT is software for collecting, checking and processing data from Road feight transport. Most measurement errors are detected and corrected by arithmetic and logical controls embedded in IS RFT . The software performs mandatory and planned control and warning in case there are errors, it displays a warning dialog inconsistencies found. The system does not allow the completion of the report until all outstanding correct mandatory controls.

Road freight data are not seasonally adjusted.

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