Reference metadata describe statistical concepts and methodologies used for the collection and generation of data. They provide information on data quality and, since they are strongly content-oriented, assist users in interpreting the data. Reference metadata, unlike structural metadata, can be decoupled from the data.
External trade statistics in goods give information about the commodity flows between Turkey and other countries. A distinction is made between the trade flows. Imports refer to goods entering the Turkish territory, exports to goods leaving the Turkish territory.
The Turkish foreign trade statistics are produced in accordance with the guidelines of the United Nations’ Statistical Commission and of the European Union.
3.2. Classification system
Product classification
Turkish external trade statistics are published in Comext according to the Combined Nomenclature (CN).
Country classification
The nomenclature of partner countries used by Turkey in original data is the ISO 3166 alpha-2 codes. These codes are trans-coded by Eurostat into EU-Geonomenclature codes (the official country nomenclature adopted by the European Union) before load the data in Comext.
3.3. Coverage - sector
All ISIC activities are covered.
3.4. Statistical concepts and definitions
YEAR: Referance year
MONTH: Referance month
EXP_IMP: Flow
COMCODE: Turkish external trade statistics are published in Comext according to the Combined Nomenclature (CN).
COUNTRY: Final destination country in export, Country of origin in import.
SPC: Statistical Procedure Codes are compliant with the EU and sent the list of SPC to Eurostat with the first month’s data.
PREFERENCE
TRANSPORT Mode of transport
CONTAINER
FLAG Flag of the carrier
EURO Statistical Value (CIF for Imports, FOB for Exports).
NETMASS Except ships, natural gas and electricity, Net mass is available for all the goods as kilogram.
SUPUNIT Supplementary unit codes are loaded according to the CN. However it cannot be guarantee that for each product code the supplementary unit used corresponds to the one requested by the CN.
UNIT Measurement units are fully compliant with the EU and sent the list of units to Eurostat with the first month’s data.
3.5. Statistical unit
Enterprise
3.6. Statistical population
Turkey
3.7. Reference area
In terms of foreign trade statistics, customs warehouse, free zones and duty-free shops in Turkey are considered as beyond the customs frontier. Trade with third countries from these areas is excluded from the statistics.
3.8. Coverage - Time
Monthly since 1999.
3.9. Base period
2003
Quantity in kilogram,
Supplementary quantity in (m³, m², pairs etc.)
Value in Euro
The reference period for the recording of external trade transaction should be the calendar month of import/export of the goods. However, in practice the reference period correspond to the calendar month during which the customs declaration is accepted.
6.1. Institutional Mandate - legal acts and other agreements
Statistics Law of Turkey (Law Number 5429) entered into force on the 18th of November 2005.
Regulation of Procedure and Principles of Data Confidentiality and Confident Data Security in Official Statistics
Official Statistics Programme 2012-2016
Strategic Plan 2012-2016
6.2. Institutional Mandate - data sharing
No agreement
7.1. Confidentiality - policy
According to the Article 13 of the Statistics Law of Turkey, passive confidentiality is used in foreign trade statistics
7.2. Confidentiality - data treatment
Turkstat has used passive confidentiality in external trade statistics. For the data considered confidential due to the indirect identification in foreign trade statistics, these confidentiality rules are implemented when a statistical unit applies with a written application requiring consideration of its data as confidential. When data is made confidential, it is kept available at the most detailed possible level of classification (keep at least the real Chapter HS2 to hide data). The need to confidentialise is assessed, periodically.
Some variables such as CN8, partner country or some crucial commodities such as natural gas on transportation code, province code in addition to commodity and partner country, Net Mass (Q1), Supplementary Units (Q2) may be confidential according to the evaluation by officials.
8.1. Release calendar
Advance release calendar are available in TurkStat web site and accessible by all the users.
Users can access to data only from Comext database.
Monthly.
10.1. Dissemination format - News release
Data set and control figures are sent to Eurostat by Edamis, there is no link to the press releases.
10.2. Dissemination format - Publications
There is no publication related to dataset sent to Eurostat.
10.3. Dissemination format - online database
There is no database related to dataset sent to Eurostat.
10.4. Dissemination format - microdata access
No dissemination of micro data
10.5. Dissemination format - other
There is no dissemination of data
10.6. Documentation on methodology
National reference metadata is available on the Turkstat web site.
10.7. Quality management - documentation
Quality reports haven’t been available yet.
11.1. Quality assurance
There isn’t a systematic quality assurance framework implemented in Turkstat.
11.2. Quality management - assessment
There isn’t a systematic quality assurance framework implemented in Turkstat.
12.1. Relevance - User Needs
There is no study on user needs about data sent to Comext.
12.2. Relevance - User Satisfaction
There is no study on user needs about data sent to Comext.
12.3. Completeness
Not available
13.1. Accuracy - overall
The main source of error is wrong information being made by traders on the SAD’s. Whenever traders aware of error, they can easily correct them with an additional declaration. These corrections are reflected to the data by Turkstat as soon as possible. The affects of these corrections to the variables are so low. Another reason of bias is late arrival of SADs to the Customs. Data from these kind of SADs are reflected to statistics following months.
13.2. Sampling error
Not available
13.3. Non-sampling error
Not available
14.1. Timeliness
Monthly data is sent to Comext shortly after disseminated in Turkey.
14.2. Punctuality
Monthly data is taken 3-4 days after the reference month from the Ministry of Customs and Trade. The percentage on the press releases delivered on time is 100%.
15.1. Comparability - geographical
Turkstat has conducted some studies by comparing Turkey’s data with some partner countries but not systematically implemented yet
15.2. Comparability - over time
Not available
15.3. Coherence - cross domain
No information provided
15.4. Coherence - internal
No information provided
Not available
17.1. Data revision - policy
Original monthly figures of the current year are revised each month. The revised figures are processed by Eurostat and loaded in Comext, were they replace the existing figures. Final data is available normally T+9 months.
17.2. Data revision - practice
Every month, previous months' figures are revised according to new data from customs, corrections on declarations made by traders, late answers from traders, corrections on ships and aircrafts, repair, goods for processing, methodological changes etc. Impact of revisions in terms of value and quantities are less than 5%. The final data is sent to Eurostat in Y+9 months.
18.1. Source data
The main source of data sent to comext is Customs Declarations (SAD). SAD’s are fulfilled by traders automatically and collected in data warehouses of Customs called GUVAS.
18.2. Frequency of data collection
Data is provided by the Ministry of Customs and Trade monthly. Registers of the Civil Aviation Agency are provided irregularly. Registers of the Banking Regulation and Supervising Agency and Turkish Exporters Assembly data is provided monthly, too.
18.3. Data collection
Data is sent by the Ministry of Customs and Trade via Cute-ftp. Some transactions on special commodities (electricity, crude petroleum, natural gas) collected by survey from the exporter/importer enterprises. For aircrafts, some additional documents taken from Agency of Civil Aviation and Banking Regulation and Supervision Agency. For analyzing exports, registers of the Turkish Exporters Assembly are used.
18.4. Data validation
Z-Score & BoxPlot
FTS group has implemented unit value checking system using credibility intervals. Intervals are based on each commodity for imports and exports, generated using two-year transactions. Intervals are available for unit value per net mass, per Supplementary unit (SU) and the ratio of net mass/SU. It is updated once a year.
All errors are reported automatically for correction. Some errors are auto-corrected if correlation table is available. These errors can be added into correlation table in SAS program for future correction.
Commodity code, Customs Procedure Codes (CPC), type of money transfer code (payment), currency code for invoice, freight, insurance, transaction price and other expenses abroad, terms of delivery, mode of transport, supplementary unit, code of nature of transaction, country of destination, country of origin, country of consignment, Customs office codes are checked automatically.
18.5. Data compilation
Registers below threhold (100 $) are excluded from statistics. Statistical Procedure Codes of these records are being changed and being kept in Database. There is no imputation used.
18.6. Adjustment
Seasonal and calendar adjusted data hasn’t been sent to Comext yet.
N.A.
External trade statistics in goods give information about the commodity flows between Turkey and other countries. A distinction is made between the trade flows. Imports refer to goods entering the Turkish territory, exports to goods leaving the Turkish territory.
The Turkish foreign trade statistics are produced in accordance with the guidelines of the United Nations’ Statistical Commission and of the European Union.
6 August 2013
YEAR: Referance year
MONTH: Referance month
EXP_IMP: Flow
COMCODE: Turkish external trade statistics are published in Comext according to the Combined Nomenclature (CN).
COUNTRY: Final destination country in export, Country of origin in import.
SPC: Statistical Procedure Codes are compliant with the EU and sent the list of SPC to Eurostat with the first month’s data.
PREFERENCE
TRANSPORT Mode of transport
CONTAINER
FLAG Flag of the carrier
EURO Statistical Value (CIF for Imports, FOB for Exports).
NETMASS Except ships, natural gas and electricity, Net mass is available for all the goods as kilogram.
SUPUNIT Supplementary unit codes are loaded according to the CN. However it cannot be guarantee that for each product code the supplementary unit used corresponds to the one requested by the CN.
UNIT Measurement units are fully compliant with the EU and sent the list of units to Eurostat with the first month’s data.
Enterprise
Turkey
In terms of foreign trade statistics, customs warehouse, free zones and duty-free shops in Turkey are considered as beyond the customs frontier. Trade with third countries from these areas is excluded from the statistics.
The reference period for the recording of external trade transaction should be the calendar month of import/export of the goods. However, in practice the reference period correspond to the calendar month during which the customs declaration is accepted.
The main source of error is wrong information being made by traders on the SAD’s. Whenever traders aware of error, they can easily correct them with an additional declaration. These corrections are reflected to the data by Turkstat as soon as possible. The affects of these corrections to the variables are so low. Another reason of bias is late arrival of SADs to the Customs. Data from these kind of SADs are reflected to statistics following months.
Quantity in kilogram,
Supplementary quantity in (m³, m², pairs etc.)
Value in Euro
Registers below threhold (100 $) are excluded from statistics. Statistical Procedure Codes of these records are being changed and being kept in Database. There is no imputation used.
The main source of data sent to comext is Customs Declarations (SAD). SAD’s are fulfilled by traders automatically and collected in data warehouses of Customs called GUVAS.
Monthly.
Monthly data is sent to Comext shortly after disseminated in Turkey.
Turkstat has conducted some studies by comparing Turkey’s data with some partner countries but not systematically implemented yet
