Policies & Methodologies
In this area you will find links to downloadable PDF versions of the published policies and methodologies relating to the collection and publication of the UK Overseas Trade Statistics (OTS). Summary detail regarding the impact of the policies and methodology on the published OTS can be viewed in 'Understanding OTS data'.
Summary presentation of UK Overseas Trade Statistics (OTS) methodology
This short set of OTS methodology summary slides (pps format) tells the story of how the OTS are compiled, quality assured and used and can be downloaded for your future reference.
Methodology paper for the Overseas Trade Statistics
This methodology paper covers all aspects of the Overseas Trade Statistics methodology – data sources, classifications and definitions, quality assurance, publications and governance. It is a useful companion to the trade data, providing the definitions and methodologies on which the data are based. The Overseas Trade Statistics Methodology paper is available here:
February 2015: Methodology paper for the Overseas Trade Statistics (pdf)
Suppression of data
Some of the collected, detailed trade data is suppressed from publication to protect sensitive business and national interests. The policy applied to the OTS is available here:
June 2014: OTS Policy Statement: Policy on Suppressions (pdf)
Current suppressed codes can be found in the Related links area
Revision of published data
OTS data are subject to scheduled revisions to provisional data (routine monthly updates) and non-scheduled revisions to final data (historic revisions) in accordance with the Code of Practice for Official Statistics and the HMRC policy on Revisions available here:
June 2013: HMRC Policy on Revisions to Data (pdf)
OTS EU data is collected via the Intrastat survey of trading businesses. An estimate is included in the published OTS on a monthly basis, to take account of trade yet to be declared.
February 2010: OTS Methodology: Enhancement of non-response estimation (pdf)
Net mass estimation methodology
From January 2010 an estimate of the quantity (net mass) will be published for those commodity codes where the Intrastat regulations do not require it to be collected from the EU trade declaration. Details of the estimation methodology are available here:February 2010
: Estimation of Net Mass Data from 1 January 2010
- Intrastat (Update)
Regional Trade Statistics (RTS) methodology
RTS were introduced in1999 to support the economic decision-making of the devolved Scottish Parliament, Assemblies and other regional bodies within the UK. These statistics provide a useful breakdown of the flows of imports and exports between regions of the UK and other countries. The collection and publication methodology for the RTS is available here:May 2015
: UK Regional Trade Statistics methodology
From January 2014, Non-Monetary Gold will be included in OTS data series. This change will occur in the January 2014 data. The first release of data affected by these changes was published on 12 March at 0930 and 18 March at 0930 for Non-EU and EU respectively.
A summary of how this affects past data and the reasons why we are doing this are outlined in the documents below: