Quality report
Period: Annual
Year: 2017

01. Contact
02. Statistical presentation
03. Statistical processing
04. Quality management
05. Relevance
06. Accuracy and reliability
07. Timeliness and punctuality
08. Coherence and comparability
09. Accessibility and clarity
10. Cost and Burden
11. Confidentiality
12. Comment

01. ContactTop
01.1. Contact organisation

Statistical Office of the Republic of Serbia (SORS)

01.2. Contact organisation unit

Agriculture and Forestry Division - Unit for livestock and fishery statistics

01.3. Contact name

Dragana Pogarcic

01.4. Contact person function

Head of Unit for livestock and fishery statistics

01.5. Contact mail address

5 Milana Rakića, Belgrade

01.6. Contact email address

01.7. Contact phone number

+381 11 2412922 ext.243

01.8. Contact fax number

+381 11 2410397

02. Statistical presentationTop
02.1. Data description

Data allow tracking of the main indicators in  the aquaculture production for national and internacional needs, namely: the structure of persons engaged on the fish holdings - by sex and  length of  realized work; capacity and structure of the freshwater facilities; the production of fish for consumption in the facilities for carp and trout breeding at first sale for human consumption, as well as price per tonne - by species, FAO major area, cultivation methods; production of fertilised eggs and juveniles at first sale for further on - growing or release to the wild - by species; watercrafts and equipment on fish holdings and certain costs of production.

Aquaculture production statistics as defined in Regulation (EC) No 762/2008 of the European Parliament and of the Council of  9 July 2008 on the submission by Member States of statistics on aquaculture and repealing Council Regulation (EC) No 788/96.    OJ L 218, 13.8.2008, p. 1-13) contain four different annual datasets:

- AQ2A - Aquaculture production volume at first sale for human consumption (excluding hatcheries and nurseries) by species, FAO Major Area, cultivation method and aquatic environment. 

- AQ2B - Production of fish eggs (roe) for human consumption at first sale by species, by FAO Major Area, cultivation method and aquatic environment.

- AQ3 - Input to capture-based aquaculture, i.e. wild seed, by species.

- AQ4 - Production of juveniles and fertilised eggs at first sale for further on-growing or release to the wild by species.

The production volume is measured in tonnes live weight (TLW) and economic value as unit price in national currency per tonne (NAC_T/TLW), with the exception of juveniles and fertilised eggs which are measured in numbers.

In addition, a fifth dataset in three-year periodicity (AQ5) provides information on the size (in hectares, 1000 cubic metres or metres) of aquaculture production facilities segmented by species group, FAO Major Area, cultivation method and aquatic environment.

Phenomena such as production of fish eggs (roe) at first sale for human consumption and input to capture-based aquaculture are not relevant for the Republic of Serbia why these data are not available.


02.2. Classification system

The following classifications are used in data production:

Classification of Activities - KD (2010) ("Official Gazette of the RS", No104/09) based on classification NACE Rev.2 (Statistical Classification of Economic Activities in the European Community, Rev. 2);

Reference year (TIME);

Reporting country (GEO) - code defined by ISO3166-1;

Species (SPECIES) - name, scientific name and 3-alfa code, by groups according  to ISSCAAP classification (International Standard Statistical Classification  for Aquatic Animals and Plants);

Production method (AQUAMETH) - according to Regulation (EC) No 762/2008;

Production area (FISHREG) - FAO Major Fishing Areas;

Aquatic environment (AQUAENV) - water types: fresh water (FRW), see water (SEA) and brackish water (BRK).

For the Republic of Serbia relevant  ‘FAO major areas’ is 5 (European inland waters). Regarding 'Cultivation method' relevant are ponds, tanks and cages in fresh water as a water type.

02.3. Coverage - sector

Covered is commercial aquaculture production destined to human consumption.

02.4. Statistical concepts and definitions

Aquaculture emphasizes the growth or cultivation of aquatic organisms, use of the techniques which is achieved by increasing the production of these organisms beyond the capacity of the natural environment.

Fish ponds, fish-walled parts of the fishing water and the cages are arranged on the land areas or fishing water intended for the cultivation and production of fish, juveniles and fertilized roe, which meet the prescribed conditions.

Fish holding is technically and economically independent production unit, which has a single management and which, as a primary or secondary activity, carries out the production of fish for consumption and juveniles for the market. Fish holding can be a legal person, entrepreneur or family holding, depending on whether it is, in accordance with the law governing the registration of business entities, registered in the Business Registers Agency to carry out the production of fish for consumption and juveniles or registered in other activitiy and  this production is performed under this status (legal entity / entrepreneur),  or not registered in the Business Registers Agency (family fish holding).

For the nacional needs, total area of ​​the fish holding includes, in addition to productive areas of the water, also cultivated land, the forest area, buildings, roads and the rest non-arable land that is used for the production in the ponds and forms an inseparable part of the fish farm.

The surface of the water in use  comprises used productive water surface in the course of the observed year, and it may be equal to or less than the total productive area.

Juveniles are individuals in the period between the completion of the development of the metamorphosis of larvae, and the acquisition of full maturity.

In accordance with Regulation (EC) No 762/2008 production of  fish for consumption and juveniles means a quantity of fish for consumption that is sent to the market (sold) during the reporting period (realized production of fish for consumption-first sale) and produced juveniles for sale. Only production for human consumption is considered. Ornamental or functional species as well as feed production is excluded.

02.5. Statistical unit

Statistical unit is aquaculture production facility.

02.6. Statistical population

Тhe target population are all commercially active aquaculture production facilities.

02.7. Reference area

Reference area is the Republic of Serbia.

Notes: Since 1999 Statistical Office of the Republic Of Serbia does not answer for  the specific data for AP Kosovo and Metohija and these data  are not included in the coverage for the Republic of Serbia (total)

02.8. Coverage - Time

Data are available from 1963. Time series has been interrupted several times. Due to harmonization with Regulation (EC) No 762/2008 most important changes were introduced in 2013.

02.9. Base period

Not applicable.

03. Statistical processingTop
03.1. Source data

Data are obtained by comprehensive regular statistical survey Anual report on production of fish for consumption and juveniles in aquaculture. The list of reporting units was optained using the Statistical Business Register of the Republic of Serbia and Evidention of aquaculture facilities of Ministry of Agriculture, Forestry and Water Management (Veterinary Administration).188 reporting units were on the list for 2017.

Data relating to the number of delivered eggs and juveniles for release to the wild - by species are estimated on the basis of  the results of the restocking from the comprehensive regular statistical survey Annual fish catch in rivers, lakes and canals. In order to provide relevant data in millions, average mass of eggs (1kg=800000 eggs) and juveniles (age-old=0.150kg; two age-old=0.950kg) are applied on quantities (kg) of eggs and juveniles released to the wild. There were not any differences in the definition of the variables between estimates and those described in the Regulation (EC) No 762/2008 as well as some special limitations and drawbacks of estimation wich could significantly affect the data quality.


03.2. Frequency of data collection

Data are collected on annual basis, in the period 10 February - 1 March of the current for the previous year.

03.3. Data collection

The survey Anual report on production of fish for consumption and juveniles in aquaculture is conducted through SORS regional offices (16). Data are collected by reporting method, by mail - using printed questionnaire, or via e-mail. Reporting units are contacted in order to provide information on the implementation of the survey and questionnaires are sent with explaining regarding deadlines and completing the questionnaire by 10 February. Reporting units are obliged to forward completed questionnaire to corresponding SORS regional office by 1 March (for follow-up interviewing deadline is 1 April). Controlled data entry is done by SORS regional offices up to 1 April. Further data processing and analysis are done centralized by 3 May when data are published.

03.4. Data validation

Automatic and manual validation  of the dataset completness are implemented. Data validation is performed on the basis of the previous year results.

03.5. Data compilation

Controlled data entry and data processing are done in program IST (developed by SORS). Non response of reporting units and non response on certain questions for key variables are solved by imputation data from the last year report of the same response unit  or from reports of other units from the current year, if it is relevant and possible.


03.6. Adjustment

Not applicable.


04. Quality managementTop
04.1. Quality assurance

General framework for quality assurance is defined by the Declaration on the quality or the Quality Policy, which can be accessed via the following link:

Quality control is carried out at all stages of data production. First of all, this control refers to a coverage control and  updating of reporting units address book. In the first phase of the questionnaires control completeness and accuracy of filled questionnaires is carried out . Further, data are controled during data entry in IST program according to the defined criteria of logical and computy control.

04.2. Quality management - assessment

Quality of data can be estimated as satisfactory.

05. Relevance Top
05.1. User needs

Users of these data are the Ministry of Agriculture, Forestry and Water Management, Agency for environmental protection, Institute of Biology, other institutions and institutes, journalists, students and other individuals.

In order to define appropriate content of the questionnaire for this survey representatives of the Ministry of Agriculture, Forestry and Water Management and other experts in this field were consulted, and EU legislation was examined, to get data that would satisfy national and international needs.

Around 80% of data requested under Regulation (EU) No 762/2008 meet national data needs. Additional data that are provided for national needs are: the structure of employees on fish holdings - by sex and  length of  realized work, watercrafts and equipment on fish holdings and  some costs of production.

05.2. User satisfaction

General Survey on user satisfaction is conducted every two years and results are available on the web site of SORS.  There is no specific survey on user satisfaction related to aquaculture statistics.


05.3. Completeness

Data are full harmonized with Regulation (EC) No 762/2008.

05.3.1. R1. Data completeness - rate

The calculated rate for producers (P) is 1.00. The calculated rate of users (K) is 0.50.

06. Accuracy and reliabilityTop
06.1. Overall accuracy

Data are obtained by full coverage of the reporting units, where non-response is a major factor that affects the accuracy of the data. Accuracy can be assessed as medium.

06.2. Sampling error

Not relevant.

06.2.1. A1. Sampling error - indicators for P (producers)

Not applicable.

06.3. Non-sampling error and

Control of the coverage of reporting units is done in SORS regional offices, included making contact with units and providing additional information regarding the filling in the questionnaire.

The first control of questionnaires is done in the SORS regional offices, too. During the control these errors are corrected on the basis of checking with certain reporting unit and thereafter controlled data entry is performed.  There is no record on the number of these errors.



06.3.1. Coverage error

The  full coverage of all active commercial facilities for aquaculture production is ensured by the creation of a unique list of enterprises (registered in the Business Registers Agency to perform the production of fish for consumption and juveniles or are registered in another activity but perform this production) and natural persons registrated by Ministry of Agriculture, Forestry and Water Management (Veterinary Administration) аs owners of facilities. The updating of the list of reporting units is carried out once in the current year with the status as at 31 December of the previous year, using the available sources (Statistical Business Register, Evidention of aquaculture facilities of the Ministry of Agriculture, Forestry and Water Management), including contacting the reporting units, field visits and conducting the survey itself. A 2. Over-coverage - rate

From the total number of units from the list (188)  0,5 % stated that are not involved in commercial aquaculture production destined to human consumption. A 3. Common units - proportion

Not applicable.

06.3.2. Measurement error

After preparation of the questionnaire  with the participation of experts in the field of fisheries, the questionnaire was tested by several reporting units, which gave a positive assessment of the clarity of content. In order accuracy of filled questionnaires, a brief explanation for the reporting units is given below each table in the questionnaire. Particular attention is given to the concept realized (sold) in the tables that relate to the production of  fish for consumption, due to the fact that the displayed amount of fish means  produced quantity in the reference year. Training of representatives of SORS regional offises who are directly involved in the implementation of this survey was held. Among other things, their task is to contact the reporting units and provide additional explanation regarding filling in the questionnaires. In the event that, despite all the action taken, questionnaire is incorrectly filled out, they are obliged to call the reporting unit and along with it to make correction. In addition, the internal analysis of data based on expected values ​​for certain phenomena - external data is carried out  (eg. semi-intensive production of the carp fish ponds range in the interval from about 700 to 1000 t / ha, in trout from 10 to 20 kg / m3 ).

06.3.3. Non response error

Unit non-response can be evaluated as moderate.

In order to reduce the unit non-response follow-up interviews are carried out (reporting units are contacted after deadline for submission of filled questionnaires). Item level non-response is reduce by imputation based on answers of similar units or by imputation based on the answers of the same unit from previous year, if it is relevant and possible. Unit non-response - rate

In relation to the total number of reporting units,  in the last survey non-response was 2,1%. A5. Item non-response - rate

Not available.

There no items with a significant (high) non-response rate. Incomplete responses mainly refer to the average price per weight unit at first sale or size of facilities.

06.3.4. Processing error

Processing errors have been removed in the process of testing applications for data entry  and formating output tables  in the IST program. A 7. Imputation - rate

There is no evidention on number of imputations.

06.3.5. Model assumption error

Not applicable.

06.4. Seasonal adjustment

Not applicable.

06.5. Data revision - policy

General policy revision was adopted by the institution, it is available on the SORS website and can be accessed via the following link:

06.6. Data revision - practice

Data revision was not applied.

06.6.1. A6. Data revision - average

Not applicable.

07. Timeliness and punctualityTop
07.1. Timeliness

For the national purposes data are published four months after the reference period. The deadline for submitting data to Eurostat is 31. December of the current for the previous year.

07.1.1. TP1. Time lag - first result

Not applicable.

07.1.2. TP2. Time lag - final results

Time lag of the final results is 123 days.

07.2. Punctuality

The information is published in a timely manner, in accordance with the defined deadlines. Data collection process start on 10 February. Deadline for data providers to respond  is 1 March. In order to conduct the follow-up interviews the deadline for data providers to respond to the survey was extended until 1 April. Processing and compilation of data for the national purposes takes 4 weeks.  Тhe deadline for the publishing of results is on 3 May of the current for the previous year. Extract data for submission to Eurostat takes 5 hours.

07.2.1. TP3. Punctuality - delivery and publication

Indicator of respect of the deadlines for publishing data is 0, while the rate of compliance with the terms of publication is 1.

08. Coherence and comparabilityTop
08.1. Comparability - geographical

There are not differences in the definition of the characteristics between national data and those described in Regulation (EU) No 762/2008.


08.1.1. CC1. Asymmetry for mirror

Not available.

08.2. Comparability - over time

Comparable-complete time series is available only from 2013.

Data on total area of carp and trout facilities and production of juveniles are availabe since 1963.  Since 1997 the available data are: employees on fish farms - total, watercrafts and equipment, the capacity of carp and trout facilities, production of fish for consumption and juveniles and consumed amount of feed and fertilizers. Since 2006 data on the number of employees by gender and length of realized working hours, production of eggs, larvae, age-old and two-age-old juveniles are collected, and since 2013 capacity of the cages, the prices on the first sale of fish for consumption per unit of measure (RSD/kg) and certain costs of production on fish holdings are available, too.


08.3. Coherence - cross domain

There are no other relevant statistical data, except data on the total number of employees in the fisheries and aquaculture activity  that are the result of survey based on combining the data of the Central Registry of Compulsory Social Insurance of the Republic of Serbia and the Statistical Business Register.

08.4. Coherence - sub annual and annual statistics

Not applicable.

08.5. Coherence - National Accounts

Not applicable.

08.6. Coherence - internal

Statistical data within the data set are consistent.

09. Accessibility and clarityTop
09.1. Dissemination format - News release

News release is not scheduled.

09.2. Dissemination format - Publications

Data can be found in the SORS complex publication "Statistical Yearbook".

09.3. Dissemination format - online database

Published data  on the site can be free accessed via the following link:

09.3.1. AC1. Data tables - consultations

Not available.

09.4. Dissemination format - microdata access

The data are available to users only in aggregated form, in accordance with the law.

09.5. Dissemination format - other

Data transmission to Eurostat is done by SDMX files. Data  for FAO are transmitted in the form of excel tables by e-mail. There are no other forms of dissemination.

09.6. Documentation on methodology

Extract of the methodology is published on SORS websajt:

Questionnaire can be accessed via the following link:

09.7. Quality management - documentation

For information on Quality Reports see section Quality assurance.

09.7.1. AC 3. Metadata completeness - rate

The rate of completeness of metadata is 0.9.

09.7.2. AC 2. Metadata - consultations

Not available.

10. Cost and BurdenTop
10. Cost and Burden

Funds for the production of relevant statistical data are provided from the budget of the Republic of Serbia. As this is in annual periodicity and there are small number of reporting units, the production costs of these data are insignificant. Estimated burden of reporting unit is 120 minutes per year (burden in total in the last reference year was 16 200 minutes ie. 270h)

11. Confidentiality Top
11.1. Confidentiality - policy

Individual data are the official statistical data and as such are confidential and subject to special protection, which is provided in all phases of  research. Confidentiality of individual data is guaranteed by the Law on oficial statistics. Any abuse of official statistics for misdemeanor charges, in accordance with the Law.

11.2. Confidentiality - data treatment

Individual data are published only in aggregated form.

12. CommentTop
12. Comment

No comment