Accredited official statistics

Regional trade in goods statistics methodology

Updated 14 November 2024

1. About Regional Trade in Goods Statistics

HM Revenue & Customs (HMRC) introduced the Regional Trade in Goods Statistics (RTS) in January 1999 to support the economic decision-making of the devolved Scottish and Welsh Governments and other regional bodies within the UK. These statistics provide a useful breakdown of the flows of goods imports and exports between regions of the UK and other countries. RTS was designed to provide a meaningful breakdown of the UK’s Overseas Trade in Goods Statistics (OTS), split by the 9 English regions and 3 Devolved Administrations, also known as the International Territorial level 1 (ITL1).

United Kingdom

• England
  • North East
  • North West
  • Yorkshire and the Humber
  • East Midlands
  • West Midlands
  • East
  • London
  • South East
  • South West
• Wales
• Scotland
• Northern Ireland

RTS includes all merchandise trade within the scope of the UK’s OTS. It therefore excludes trade in services (e.g. banking, tourism), intangibles (e.g. financial investments or transfers) and the movement of goods between regions of the UK.

Following customer feedback, from March 2018, HMRC published ‘Experimental Statistics’ based on UK geographical areas smaller than the International Territorial Level 1 (ITL1) regions used in the RTS. The employee allocation method used in the RTS was replicated to this data so the new figures neatly aggregate to the published RTS ITL1 figures. The UK regional trade in goods statistics disaggregated by smaller geographical areas can be found on GOV.UK.

In 2015, a public consultation of the RTS methodology and publication was carried out.

The main reasons for reviewing the RTS were:

• To ensure the statistics produced are fit for purpose and still required by users;
• To look at options that improve the usability and quality of the statistics produced;
• To harmonise, where possible, with the methodologies employed for other regional based statistics produced across the Government Statistical Service (GSS);
• To identify the right balance between producing statistics at regions / locations, with product and partner country; but still ensuring disclosure controls; and
• To improve the accuracy of the count of number of businesses, incorporating additional data sources if possible.

A total of eight responses were received, including several government stakeholders of these statistics. All respondents to the consultation were in favour of continuing with quarterly RTS as there were no alternative published data sources that could replace it.

During the consultation, regional allocation methodology was also reviewed and the majority of the respondents preferred that regional allocation of a business’ trade be carried out using IDBR (Inter-Departmental Business Register) data and based on the proportion of a business’ employees in a region, rather than allocating trade entirely to a region where a business’ head office was located. As a result, change in regional allocation methodology was implemented from Quarter 3 (Q3) 2016 onwards.

The respondents also considered the inclusion of business counts in RTS very important. Prior to the consultation, the business counts for EU traders were partially captured as it only included Intrastat declarants. Following the consultation, RTS included complete counts of the UK businesses that have trade activity with both EU and Non-EU countries.

2. Recent changes to RTS

2.1 Changes in data sources

Up to 31 December 2020, statistics for the UK’s trade in goods with EU were collected via the Intrastat statistical survey, which required traders to declare the value and volume of commodities traded with EU Member States within the relevant month of physical goods movement.

Businesses that move goods to or from the UK to/from non-EU countries must complete a Customs declaration. HMRC uses the details from these declarations to compile statistics for the UK’s goods trade with non-EU countries. This is unchanged. However, there have been two changes in the data sources for GB-EU trade since 2021:

Exports

For goods moving from 1 January 2021, GB to EU export statistics are compiled directly from customs export declarations according to the requirements of the Taxation (Cross Border Trade) Act. The customs declaration requirements are more complex than the single monthly aggregated Intrastat return and can result in differences between dates of declaration and actual movement of the goods out of the country. Intrastat survey returns, however, continued to be collected for goods exported from Northern Ireland (NI) to the EU, under the terms of the Northern Ireland Protocol.

Both the GB to EU customs export declaration data and Northern Ireland (NI) Intrastat export (dispatch) data were incorporated into the overall UK to EU export dataset. As a result of the changes and differences outlined above, there was a break in the timeseries for published UK to EU export statistics from January 2021.

Imports

During 2021, the Intrastat survey continued to operate for all UK (GB and NI) imports (arrivals) from the EU, to mitigate the effects of staging customs controls, and to comply with the Northern Ireland Protocol.

From January 2022, the UK’s goods imports from EU dataset incorporates two data sources: Great Britain’s (GB) imports from EU data that is collected via Customs declarations and Northern Ireland’s (NI) imports from EU data collected via Intrastat declarations.

As announced in the Borders Control Statement (UIN HLWS473) on 15 December 2021, the Government extended the current arrangements for moving goods from the island of Ireland to Great Britain for as long as discussions on the Protocol are ongoing.  These temporary arrangements enable Irish traders to continue relying on staged customs controls for the foreseeable future. While these measures are in place, import statistics for trade between GB and Ireland are reported as declared and may not reflect the period in which the goods have been traded.

As a result of the changes and differences outlined above, there is a break in the timeseries for published EU to UK import statistics from January 2022.

2.2 Changes in statistical value threshold in customs declarations

Customs declarations with commodity line values that fall under the statistical value threshold of £873 (in value) and 1,000kg (in net mass) are aggregated into ‘low value aggregates’. The Trade Statistics and Customs Analysis (TSCA) team do not receive business, product or partner country information on these movements. As a result, TSCA cannot assign this trade to a UK region, therefore the value is assigned to the Unallocated-Unknown region. This applies to goods exports from GB to EU countries from 2021, and imports into GB from EU countries from 2022. This is consistent with the RTS methods used for trade with non-EU countries, which are also sourced from customs declarations.

As a result of this change, a value increase will be apparent for Unallocated-Unknown region for EU flows from the dates specified above.

2.3 Re-introduction of EU business counts

Due to the recent changes to data sources, a new method for EU business counts has been introduced in the 2022 Quarter 1 (Q1) publication, which results in a break in series from previous RTS EU business counts. EU and total business counts from the 2021 data period onwards will therefore not be comparable with RTS business counts published prior to 2021.

Prior to 2021, EU business counts were compiled from Intrastat declarations, while businesses trading below the Intrastat threshold were captured through VAT data. Businesses trading below the Intrastat threshold made up a small percentage of the total trade value but accounted for most of the businesses trading.

From January 2021, changes were made to the VAT data which meant that only movements between NI and EU countries were recorded. Further, following EU Exit, trade between GB and EU countries has been reported through Customs Declarations rather than Intrastat. Customs declarations therefore became the main data source for GB exports to EU countries from January 2021, and GB imports from EU countries from January 2022.

As a result of the changes outlined above, a new time series for EU business counts begins from the data period of 2021 Q1. EU business counts are now compiled in the following way:

EU exporters

From 2021 onwards:

• GB exports to EU countries via customs export declarations.
• NI exports to EU countries via Intrastat (above threshold) and VAT data (below threshold).

EU importers

For 2021:

• UK imports from EU countries were collected via Intrastat.
• NI imports from EU countries for those below the Intrastat threshold collected via VAT data.
• Additional raw customs import declaration data to better capture the GB imports from EU countries. Throughout 2021, businesses could defer their EU imports declarations for up to 175 days, this may impact data quality.

For 2022:

• GB imports from EU countries via customs import declarations.
• NI imports from EU countries via Intrastat (above threshold) and VAT data (below threshold)

2.4 The change in system of recording trade statistics

From May 2016, there was a methodological change to the way trade in goods statistics are compiled. Following a change in legislation, trade-in-goods statistics switched from the ‘general trade’ system of compilation to the ‘special trade’ system.

2.5 Regional allocation methodology

Prior to Q3 2016 RTS publications, RTS methodology generally allocated trade to a region based on where the headquarters of a business is located for VAT/Customs purposes, supplemented by an historic survey of the top 200 businesses of their locations around the UK in order to apportion their trade to the regions. The new methodology form Q3 2016 onwards allocates trade to a region based on the distribution of employees of a business across the UK. This improvement harmonised RTS methodology with other regional statistical products from across the GSS and is considered a much more proportionate reflection of trade at a regional level.

2.6 Changes in the Combined Nomenclature

Changes in Combined Nomenclature commodity codes may introduce breaks in the time series. Where an existing commodity code is essentially split so that a new commodity is created, then at the Standard International Trade Classification (SITC) Division level the amount of trade within that Division is unchanged. It is extremely rare for commodity codes to move from one Division to another unless part of a planned overhaul of the SITC managed by the United Nations. The last SITC revision (SITC Rev. 4) was implemented in 2007.

3. Relevance

RTS is compiled to serve the needs of many users, including governments, business community, compilers of other economic statistics, various regional and international organisations, researchers and the public at large. They are used to measure the trade in goods for each UK region which may help identify new trade opportunities for products across the world, to measure market share, to identify growth areas, to forecast trade and to analyse patterns.

RTS is regarded as an important indicator of the economic performance of the UK regions. Export data in particular is used as an indicator of the state of health of the UK manufacturing industry. The statistics are also used to answer press queries, parliamentary questions and Freedom of Information requests. Other Government Departments rely on HMRC’s trade data to inform evidence-based policies.

4. Timeliness and Punctuality

RTS is a quarterly publication with a brief commentary, summary tables and charts which can be accessed via UK regional trade in goods statistics. RTS data is also available in greater detail via interactive tables hosted on the UK Trade Info website.

RTS data are released on a quarterly basis. Figures are published within 12 weeks of the end of the reporting period. This is to allow time to compile, quality-assure and produce the statistics while ensuring they are timely for users.

In accordance with the Code of Practice for Statistics, the release calendar for the Regional Trade in Goods Statistics publications is compiled and published twelve months in advance of the actual release. The release calendar can be viewed alongside other HMRC publications on GOV.UK.

5. Strengths and limitations

RTS is derived from OTS data and its methodology makes use of transaction information such as commodity code, value of trade (in £), weight of trade (in kg), partner country/country group and other data fields. It also uses business information such as the business’ postcode and data from the Inter-Departmental Business Register (IDBR) provided by the Office for National Statistics (ONS).

Trade below the Intrastat threshold is contained within the OTS in the form of ‘below threshold trade allocations’ (BTTAs) and is also included within the RTS methodology. Although these BTTAs do not contain business information, the same methodology used in the OTS to calculate BTTAs is replicated in the RTS.

Where businesses are not VAT-registered, there is no mechanism in place to collect information on trade movements (this affects NI trade in goods with EU only). These trade flows are therefore not included in either the EU OTS or RTS figures.

A change in legislation on 1st May 2016 affected the way in which goods are declared to Customs, therefore UK trade statistics are prepared on the special trade basis. Under the special trade system, goods imported into customs warehouses and free zones are only recorded once they are removed and enter free circulation or certain customs procedures (e.g. Inward Processing). Re-exports from customs warehouses and free zones are not recorded under the special trade system. Prior to this, UK trade statistics were compiled on a general trade basis.

6. Data Sources

The data required for the allocation of Trade in Goods statistics to regions are taken from various sources within HMRC and the ONS.

From HMRC, Customs declaration data, Intrastat Survey, Departmental Trader Register (DTR) and VAT declaration data are used. From ONS, the Inter Departmental Business Register (IDBR) and National Statistics Postcode Lookup data (NSPL) are used.

In order to produce the RTS, the business is matched against data held in the IDBR. Where there is no match, a further match is tried agaom the National Statistic Postcode Look-up (NSPL) file. This replaced the use of the ONS All Fields Postcode Directory (AFPD) used in the previous methodology due to changes in GSS guidelines. Aggregation at the product level is achieved by matching commodity information with various accepted classification systems. These data sources are described more fully below.

6.1 Inter-Departmental Business Register (IDBR)

This database is a comprehensive list of UK businesses liable for VAT/PAYE, used by government for statistical purposes. Specific use is made of the local unit file which contains details of employment and location details of each branch of each business. This file is the key to the new methodology where trade of multi-branch companies is allocated to different regions based the location of that business’ employees.

Following advice from other GSS statistics producers who use a similar methodology, the RTS methodology uses an annual update to ensure timeliness of postcode data.

6.2 National Statistic Postcode Look-up (NSPL) file

Where there is no match against the IDBR, trade is matched against the National Statistic Postcode Look-up (NSPL) file. This file matches geographic units such as regions, counties and unitary authorities to 8-digit postcodes in the UK. The postcode of the business is matched against the contents of the postcode database, to allocate a region to the trade of that business. Also, an update is carried out to ensure consistency of postcode data.

6.3 HMRC Departmental Trader Register (DTR)

This database contains administrative details on every VAT-registered business in the UK (of which there are more than 2 million). The DTR is used to match the VAT registration number and branch identifier of the business to the current postcode recorded for that business. The trader register is updated monthly and is used to assist the matching of businesses with the NSPL.

6.4 Commodity correlation tables

UK trade figures presented within the OTS publications are broken down by 8-digit Combined Nomenclature (CN8) descriptions, which are grouped within the Standard International Trade Classification (SITC, Rev. 4) 5-digit headings.

The introduction of regional breakdowns within the RTS methodology makes it necessary to aggregate commodity code information for two main reasons.

First, the presentation of RTS figures is simplified if all CN8 descriptions can be combined within a manageable number of higher levels.

Second, aggregation helps to ensure business confidentiality. The system for aggregation within RTS is based on the SITC (Rev. 4) 2-digit headings (called ‘SITC Divisions’). A list of SITC Divisions is contained in Annex B.

For regular outputs, each unique CN8 code is correlated to one unique SITC Division. Being an internationally accepted classification system that forms the basis for the publication of OTS figures, SITC is the system of choice to use within the RTS methodology. The SITC correlation is managed by the United Nations.

7. Methodology

RTS is closely linked to the OTS, users may find the OTS methodology also helpful.

7.1 Collecting business specific data

The methodology collects a list of the VAT Registration of all businesses making imports or exports each month. The initial merge is with the IDBR, the secondary merge with the NSPL postcode file.

7.2 Collecting trade declarations data

The methodology collects all lines of trade made for the month of account from the OTS data systems. The category fields include the month of account, flow (import or export), the business’ reference (the VAT registration number), the partner country, the commodity code of the goods (in Combined Nomenclature 8-digit form), whether the statistics require suppression e.g. for military goods.

The statistical data fields are the ‘statistical value’ of the shipment (in £) and its weight (in kg, excluding packaging). Note that for the data collected by the Intrastat survey, the ‘statistical value’ of the shipment is a figure calculated by HMRC from the declared invoice value submitted by the business plus data on delivery terms. This adjustment is to reflect the value of the shipment as at the boundary of the UK customs territory and is consistent with the ‘special trade’ method of international trade accounting.

7.3 Merging data sources

There is a two-stage matching process that matches a business’ trade to a region.

• Allocate trade to a region based on its employment within each region

This method allocates trade to a region based on its employee count in each region. Where a business has branches in more than one region, its trade is proportionally allocated to each region based on the proportion of its employees in each region. Breakdowns of that business’ trade by commodity and partner country are applied uniformly across each region. Where a business has one branch (or multiple branches which fall in just one region) all their trade is allocated to that region.

• Allocate trade to a region based on postcode

If the business does not match with the IDBR, the methodology matches the business information and trade data with the contents of the ‘National Statistics Postcode Look-up’ file. This match is either at 9-digit VAT Registration Number or EORI (Economic Operators Registration and Identification) number for the location of the Head Office. See below for more details.

7.4 Matching regionalised data with other fields

Data are merged with the CN8/SITC correlation table to introduce a 5-digit SITC code for each CN8 code. The SITC code is then truncated to 2-digit level (SITC Division) to produce outputs.

Data are matched with country groups as defined within the UK statistical reporting system. Producing outputs based on country groups, rather than on individual countries, are sometimes useful where a query demands more detail at the commodity or regional level. Grouping countries into one of eight continents or country groupings e.g. EU27, renders the outputs less disclosive.

To ensure that all calculations have been carried out correctly, consistency checks are conducted at each point of the matching and aggregation process, so that any discrepancy can be quickly identified and resolved.

Explanation of matching geographic information within the RTS:

Step 1: Is the business 9-digit VAT Registration Number (VRN) or EORI present?

If yes go to step 2

If no, there cannot be a postcode match and the trade is classified to ‘Unallocated-unknown’. Missing VAT/EORI numbers may arise because the business has omitted to fill out the relevant box, or because a forwarding agent has submitted a declaration on behalf of the business and has left the VAT/EORI registration box blank.

Step 2: Is the business on the Interdepartmental Business Register?

If yes go to step 3

If no go to step 5

Step 3: Does the business have one branch on the IDBR?

If yes, allocate business’ trade to the Government Region of that branch

If no, go to step 5

Step 4: Does the business have more than one branch on the IDBR?

If yes, use the IDBR to calculate that business’ number of employees within each region and across the UK. Calculate the proportion of business’ employees in each region. Allocate a business’ value of trade to each region using the proportions calculated above. A business’ trade by Partner Country and commodity is allocated uniformly based on these proportions.

Step 5: Can the VAT/EORI number be matched at Head Office level with the DTR?

If this produces a valid VAT/EORI number according to DTR then the postcode information is retrieved from DTR and go to step 6.

If not, then the trade is classified to ‘Unallocated-unknown’.

Step 6: According to the ONS ‘National Statistics Postcode Lookup’, is the business’ postcode valid?

If yes, the methodology will adopt the ONS geographic information.

If no, the methodology will attempt to match at the next level postcode. For example, the postcode ‘SS99 1ZZ’ would be trimmed to ‘SS99 1Z’. If no match is found again, it is further trimmed to ‘SS99 1’, at which point postcodes beginning with ‘SS99 1??’ are identified as Southend-on-Sea, Essex, East of England Region. This process iterates up as far as 2-digit until the first match is found. If no postcode match is found, the trade is classified to ‘Unknown region’.

7.5 Incomplete or incorrect business information

The quality of RTS outputs is to a large part dependent on the accuracy and completeness of OTS data. Within HMRC Trade Statistics, significant efforts are made to assess the quality of the statistical information provided by businesses and agents on the supplementary declarations, while Customs processes provide checks on the single administrative documents. These procedures are used to quality assure the OTS outputs.

Looking specifically at RTS, the two fields that are essential for the matching process to work are the business VAT/EORI number and the postcode fields. Allocation of business to a region may not be possible, depending on the outcome of the matching procedure.

7.6 Regional allocation

Where a business has branches in more than one region, that business’ trade is allocated to each region based on the proportion of their total employees in that region. These proportions are applied uniformly across the commodities that the business trades in and similarly for partner countries. Where there is no match with the IDBR the postcode of the business’ head office is obtained from the DTR and the business then allocated to a region based on the NSPL.

7.7 Natural gas and electricity

Trade data relating to natural gas and electricity is obtained directly from pipeline and grid operators. Therefore, the appropriate methodology here is to allocate to the region where it enters or leaves the UK based on information supplied by the operators.

Natural Gas in a Gaseous State (CN8 27112100)

Flow	Notes
EU Imports	All trade allocated to East as enters UK via Bacton Interconnector
EU Exports	Exports to Belgium allocated to East via Bacton Interconnector
EU Exports	Exports to Ireland allocated to Scotland via Moffat Interconnector
EU Exports	Exports to Netherlands allocated to East (trade from Markham gas field) or East Midlands (trade from Wingate gas field) based on information from gas terminals
Non-EU Imports	Allocated to Yorkshire & the Humber (trade via Easington) or Scotland (trade via Peterhead)

Electricity (CN8 27160000)

Flow	Notes
EU Imports	Trade from France is allocated to South East (Folkestone)
EU Imports	Trade from Netherlands allocated to South East (Isle of Grain)
EU Imports	Trade from Ireland allocated to Wales (Deeside) or Northern Ireland (Strabane, Enniskillen and Tandragee) based on information from electricity terminals
EU Imports	Trade via Jersey allocated to ‘Unallocated – Known’ as per methodology
EU Exports	Trade to France allocated to South East (Folkestone)
EU Exports	Trade to Netherlands allocated to South East (Isle of Grain)
EU Exports	Trade to Ireland allocated to Wales (Deeside) or Northern Ireland (Strabane, Enniskillen and Tandragee) based on information from electricity terminals

7.8 Crude oil trade

Where oil is processed on rigs in the North Sea and dispatched directly to other countries, the oil does not enter the UK and therefore does not obtain any regional coding. The RTS methodology categorises this oil trade based on the location of the oil rig. This allocation also uses information from the Scottish Adjacent Waters Boundaries Order 1999.

Oil imported or exported into or out of the UK via ship will be associated with a business. Trade is allocated to the region where the business is registered subject to the main allocation method outlined above.

7.9 Treatment of unusual trade

There are a number of categories of trade that present difficulties in terms of assigning regions to the business or activities responsible for the trade flows. These are described below. These are recorded in the ‘Unallocated’ category, split ‘Unallocated – Known’ where full details are known but it is not realistic to allocate it to a region; and ‘Unallocated – Unknown’ where not enough detail is known to allocate to a region.

7.10 Overseas businesses registered in the UK

There are a number of businesses who act within the UK on behalf of foreign companies overseas, operating as ‘ghost presences’. For ease of administration, the majority of these businesses are registered for VAT purposes with Customs House, Aberdeen. The RTS methodology categorises this ghost trade as ‘Unallocated-known’, as allocating it all to Scotland would falsely inflate the Scottish share and we do not have any information to enable us to re-allocate these data to other regions.

7.11 Private individuals’ trade

Where individuals are importing goods via Customs Declarations, the declaration will not contain a valid business reference number, but an alternative number which is usually prefixed by P (for internal administrative purposes). These individuals do not provide other address and postcode information; therefore, the trade within this category cannot be allocated to a specific region. The RTS methodology categorises this trade under ‘Unallocated - Unknown’.

7.12 Non-registered entities’ trade

This category reflects trade carried out not by individuals but by entities that for whatever reason are not registered for VAT. No address information is available. The RTS methodology categorises this trade under ‘Unallocated - Unknown’.

7.13 Government trade

Government departments (including Health Authorities) carry out some international trade, the information for which is classed under dummy business references. This trade is classified by the RTS methodology under ‘Unallocated – Known’.

7.14 Channel Islands and Isle of Man trade

For the purposes of the OTS, ‘United Kingdom’ is defined as Great Britain, Northern Ireland, the Isle of Man, the Channel Islands and the Continental Shelf (UK governed area of the North Sea). Therefore, the OTS excludes trade between these different parts of the UK but include their trade with other countries. The Channel Islands (CI) and the Isle of Man (IoM) do not belong in a political or administrative sense to any particular UK Government Office Region. For RTS purposes overseas trade carried out by CI and IoM is therefore classified as ‘Unallocated - Known’.

7.15 Parcel Post

Parcels sent through the international post system with a value less than £2,000 require only a simplified declaration to allow transit through customs and the calculation of taxes. Declarations are made on forms which are attached to the package. An estimation system calculates a value of such trade by partner country based on information supplied by Parcel Force and the ONS.

This system is only in place for trade captured by Customs declarations and classified as ‘Unallocated Known’. For trade collected via Intrastat, if a business is above the threshold, postal transactions are included in a business’ monthly declarations in the same way as goods moving by other means of transport.

7.16 Below Threshold Trade Allocations (BTTA)

BTTAs are calculated for trade flows that are collected via the Intrastat survey. The RTS methodology, takes the OTS BTTA values and allocates them to regions as described below.

For trade collected by Intrastat survey, businesses below the Intrastat Supplementary Declaration threshold (below-threshold business) are not required to submit details of their Intrastat trade to HMRC. Estimates known as ‘below threshold trade allocations’ are made. These are broken down by partner country and commodity (HS2 and SITC2) and are included in OTS. It is assumed that the distribution of below-threshold trade by partner country and commodity is similar to the distribution of trade carried out by businesses who are just above the Supplementary Declaration Threshold (this is known as ‘just-above threshold trade’ or JATT). The methodology is implemented separately for arrivals and dispatches and produces monthly allocations.

Each month the BTTA allocation factors are calculated for each combination of 4-digit commodity code and country; these are based on the Intrastat trade received on Supplementary Declarations for the same month the previous year. Each factor represents the proportion of total trade in that commodity/country combination that is attributable to JATT.

Initial BTTAs are then derived by multiplying the total trade received in each 8-digit commodity code and country combination by the appropriate factor. These initial allocations are scaled uniformly to ensure they add up to the required BTTA total for the month. These are then aggregated to HS2 and SITC2 for publication.

When the OTS monthly releases for a calendar year are revised for the final time, at the time of the June release of the following year, the monthly BTTAs are re-scaled to match the revised BTTA total for the year, taking account of amendments to VAT returns and retrospective additions to the Intrastat register.

Prior to 2021, the sum of the JATT for a period is calculated by adding up all the Supplementary Declarations for each business over the period, then selecting the trade from the smallest businesses, ascending until the BTTA total is just exceeded. The JATT is calculated separately for Northern Ireland (NI) and Great Britain (GB), then combined.

However, for Arrivals the way sum of the JATT is calculated in OTS from 2021 has changed because VAT return only captures NI-EU trade. Therefore, during this extended period of using Intrastat for GB-EU imports, a different methodology applies. This involves applying an average initial non-response rate based on historical records (6% for arrivals), which will be reviewed as a clearer picture arises from customs declarations, as staged controls are phased out. This does affect how BTTA are calculated for Dispatches trade as both Intrastat and the VAT data covers NI to EU exports only.

The implication of this for the RTS is running the same process as for the OTS, however allocation factors are created for each combination of 4-digit commodity code, country, and additionally ITL1.

The ITL1 region is taken from the division of declared trade by the RTS in the same month previous year. Initial allocations are then also created at the HS2, SITC2, country and ITL1 combination level. The actual level of below threshold trade in each ITL1 region is also calculated by splitting the global declarations for businesses not on the Intrastat register that month by the same process used for businesses above the Intrastat threshold.

The initial allocations are ranked so that the HS2 / SITC2 / country combinations precisely equal those in the OTS, and so that the amount of below threshold trade allocated to each region closely matches the actual level of below threshold trade in each region calculated above.

Due to changes to the VAT data source, all BTTA is allocated to the NI region. This applies to dispatches trade from 2021 and arrivals trade from 2022. Although there will be instances where businesses are located in GB but moving goods (below the Intrastat threshold) between NI and the EU, due to the unreliability of VAT data for GB regions, the assumption is that all BTTA trade is carried out by businesses in the NI region.

8. Business counts

For reasons of confidentiality, HMRC does not publish business counts at detailed level for RTS. Instead, a separate table has been devised that provides information on the business population in each region. Businesses that are active in both EU and non-EU markets are counted once only in the total business counts. Businesses that are active in more than one UK region are counted in each of these regions in the total business count.

Initially there are two methods of dealing with businesses that have branches in multiple regions.

• Whole Number Method

A business will be counted as one in every region they have employees. This represents the actual count of businesses in any region. However, it will mean the sum of the business count for each region will be greater than that for the UK.

• Proportion Method

A business will be counted as a fraction in each region they trade based on the proportion of their employees in each region. An individual business counts as one business in the UK. The sum of businesses (whole and fractions) gives the total business count for a region.

Due to the recent changes to data sources, a new method for EU business counts has been introduced in the 2022 Q1 publication, which results in a break in series from previous RTS EU business counts. This is explained in detail above under Re-introduction of EU business counts section.

9. Revisions, Exclusions and Suppressions

9.1 Revisions

RTS methodology includes trade amendments for previous months, as published in the OTS, so that the outputs generated at any one point in time contains as much up-to-date information as is possible.

The addition of these items means that revised data for previous months continue to be provisional and open for revision until the trade year is officially ‘closed down’ in the following June’s month of account. For example, trade data relating to 2020 are not finalised until August 2021 publication, and may change in each intervening month. Fully revised data are published on UK Trade Info to ensure consistency with other published outputs, including the quarterly press release.

Exceptionally, HMRC may find large errors or significant values of missing data in earlier years. In these cases, it may be decided that the earlier series should be revised. Users will be informed of these revisions via UK Trade Info.

9.2 Exclusions

RTS includes all merchandisable trade within the scope of the UK’s OTS with the exception of trade in Non-Monetary Gold. It therefore excludes trade in services (e.g. banking, tourism), intangibles (e.g. financial investments or transfers), and the movement of goods between regions of the UK. It also excludes estimates for MTIC (Missing Trader Intra-Community) and late response.

9.3 Suppression

The suppression regime operates to ensure that movements of particular transactions cannot be identified. Suppression is also applied to ensure that published RTS data, whether in the quarterly press release or on the UK Trade Info website, are at a level that protects business’ confidentiality.

The full ‘Suppressions and Confidentiality’ policy for published trade data can be found on UK Trade Info.

9.4 OTS suppression policy

OTS figures published at the CN8 level and grouped by SITC 5, follow suppression principles as set out in legislation on trade statistics. This permits ‘passive’ confidentiality which means an individual business may request that HMRC suppress trade figures within a particular commodity code. Suppression is usually agreed where the applicant’s trade forms a major part of the trade within that commodity code or where they are one of only two or three businesses in the area. In addition, HMRC may suppress defence goods on the grounds of ‘military secrecy.’

The suppression may only affect the partner country or weight, depending on the outcome of the analysis. The application of suppression will determine the presentation of the statistics, depending on whether the value, weight, partner country or any combinations of these are suppressed. However, the important point to note is that suppression acts at the CN8 commodity level because this is the lowest level of detail for published outputs. For OTS outputs aggregated to SITC 4- digit or higher, suppression is not required.

9.5 RTS suppression and confidentiality policy

RTS has confidentiality and disclosure restrictions applied in order to comply with the National Statistics Code of Practice. RTS data are only available at SITC division (2-digit).

It is inevitable that the use of suppression will in some cases limit the detail that can be provided in the range of outputs available.

RTS data is not available for all partner countries. In the current methodology, data is available for a country only if the country’s total trade (Imports and Exports combined) exceeds one per cent of the total trade of that country’s World Region (based on a historical baseline). However, this suppression policy does not apply to EU countries where data for all member states is available. A full list of suppressed and unsuppressed countries can be found in Annex D.

10. Annexes

A series of annexes accompany this document and cover:

• format
• SITC divisions
• Commodities and transactions not classified elsewhere in the SITC
• Suppressed countries on RTS