Suppressions policy

This section is Guidance

This should be read by all users of Overseas Trade in Goods Statistics (OTS). It is the statement of the Suppressions Policy of the Trade Statistics area of HM Revenue & Customs (HMRC).

Introduction

A suppression is the concealing of potentially disclosive information from the public. OTS data published by HMRC is potentially disclosive.

Disclosive data is any data that can

  • reveal the commercial activities of a business, or
  • if published be against the national interest.

It may therefore be necessary to withhold the publication of such statistics. This disclosive data would then be aggregated to a higher level of detail so that such inferences could not be made.

Aim of this policy

The aim of this policy is to allow for publication of as much detailed trade data as possible, while protecting sensitive business and national interests through preventing disclosure where there is a clear requirement to do so.

This statement is published to inform data users or disseminators about suppressions made to published trade data and the basis for their application.

HMRC aims to ensure that users or disseminators of published trade in goods statistics data are aware of the following:

  • what suppressions are, the reasons for suppressing data, and the differences between the types of suppression;
  • the differences between the three levels of suppression applied by HMRC;
  • how applications for suppression can be made and evaluated;
  • how suppressions are applied and publicised;
  • how reviews of suppressions are conducted including the nature of correspondence between HMRC and businesses.

Policy details

Confidentiality Systems

There are two main types of Confidentiality System used in Official Statistics.

An ‘Active’ confidentiality system involves evaluating all data.  Data that can reveal the commercial activities of an individual business will be automatically suppressed. This is the standard for Official Statistics.

Under ‘Passive’ confidentiality, data is only suppressed if a request for suppression is granted.  Under a passive confidentiality system it is perfectly acceptable to publish disclosive data.  Any data for which a suppression has not been requested, regardless of whether such data reveals commercial activities or not, will be published.

When publishing the OTS, HMRC follows a system of passive confidentiality.  Requests for suppressions from a business or government department are evaluated and applied at 8-digit commodity code[1] level.

Due to this requirement OTS are exempt from the active confidentiality normally applied under the UK Statistics Authority’s Code of Practice for Official Statistics.

Types of Suppression

Commercial Suppression

This is applied when businesses believe publication will undesirably reveal details of their trade (supply, trade levels and unit costs) to competitors or customers.  It is applied at the request of the reporting businesses themselves. Businesses can be specific about the level of suppression they desire, or give details of the particular published statistics they do not wish to be disclosed (therefore specifying a level indirectly). 

Strategic Suppression

This is requested by other government departments and agencies, which believes that publication of detailed information would be against the national interest.

Levels of Suppression for a specific commodity code

There are three levels of suppression that can be applied.

HMRC is committed to protecting the interests of the individual business, but also to publishing the trade statistics to the fullest extent possible aim to release as much information as possible, whilst ensuring a traders right to confidentiality is maintained. Our aim is to publish the most detailed information, whilst maintaining confidentiality for the individual business. We will evaluate which of the three levels of suppression should be applied to achieve this aim. Suppressions are applied at commodity code level for a specific suite[2]. Quantity data refers to net mass and supplementary unit data where these units are required for that particular commodity code under that specific suite.

Level 3: Countries, Ports and Quantity for Total Trade

Value is published for total trade in the commodity code, but there is no value breakdown for partner country and port. There is complete suppression of quantity, that is, no quantity data is published at partner country and port level or for total trade.

Level 2: Countries and Ports

Value and quantity are only published for total trade in the commodity code.  Both value and quantity of trade with all concerned partner countries and ports are suppressed.

Level 1: Complete Suppression

No statistics are published for the specific commodity code.

Application for Commercial Suppression

In order for a suppression request to be considered, the businesses reporting the trade in the UK, via either the Customs or Intrastat systems, must supply HMRC (uktradeinfo@hmrc.gov.uk) with the following details:

  • full business name and VAT number;
  • contact details;
  • details of their perceived trading position.

For example, they must declare that they believe they are a ‘sole exporter or importer for a commodity’, ‘sole exporter or importer to or from a specific partner country or countries’, ‘sole exporter or importer of a specific port’ and so on.

Suppressions can be applied on commodity codes in which businesses currently trade, and also those in which they expect to undertake trade in the near future.

Further information can be obtained by contacting uktradeinfo@hmrc.gov.uk

Suppression Application Evaluation

Commercial suppressions are accepted or rejected based on the ‘value’ and ‘quantity’ of a requester’s trade both in terms of the overall market, and the market within individual partner countries and UK ports. This information is used to allocate a level of suppression in each case.  Explicitly, the details of a requester’s trade are checked against specified criteria for each level of suppression for eligibility. HMRC will aim to implement a level of suppression that publishes the most detailed information, whilst maintaining confidentiality for the individual business.

Strategic suppressions are applied by HMRC at the request of another government department, to protect the national interest.

Fulfilling criteria and obligations for suppression

If an application for a commercial suppression has been made and a requester’s trade fulfils the necessary criteria, HMRC will raise a suppression at the most appropriate level. Businesses may request a suppression at a specific level but their trade may not fulfil the criteria needed for that particular level of suppression. In such cases, HMRC will offer and subsequently apply suppression at a more appropriate level if possible.

There may be cases where the trade for an individual business comes close to fulfilling the criteria for suppression at a specific level.  Such cases will be further reviewed, and the Lead Statistician will make a judgement on whether suppression is required and, if so, at what level.

All requests for strategic suppression are discussed with the requesting government department, with mutual agreement to the appropriate level of suppression.

Applying Suppressions

Suppressions are allocated to data at 8-digit commodity code level.  These suppressions are then automatically applied at the more aggregated level of the 6-digit and 4-digit Combined Nomenclature (CN), and 5-digit and 4-digit Standard International Trade Classification (SITC). 

No suppressions are applied on data that has been aggregated at a higher level, namely SITC 3-digit and HS 2-digit (Harmonised System).

The commodity code for which the suppression is requested is known as the ‘target’.  A number of commodity codes can be grouped together under a higher-level SITC heading.  In order to prevent trade details of the suppressed commodity code being calculated by a process of deduction, it is usually necessary to apply a similar suppression to another commodity code within that group. This second suppressed code is known as the ‘mask’. 

Regional Trade in Goods Statistics

Regional Trade in Goods Statistics (RTS) data is only available and published at the aggregated SITC division (2-digit) level for Sections 1 to 8 and at Section level (1-digit) for section 9 of the SITC. No further suppressions are applied to published data. As RTS data is only published at this aggregated level, none of the commodity code based suppressions used in OTS are applied to RTS data.

Currency of Invoicing (Non-EU only)

Currency of Invoicing (COI) data is only available and published at the aggregated SITC Section (1-digit) level for four major currencies (plus ‘other’). No further suppressions are applied to published data. As COI data is only published at this aggregated level, none of the commodity code based suppressions used in OTS are applied to COI data.

UK Trade in Goods by Business Characteristics

These statistics are subject to active disclosure controls with a threshold (based on business count) and a p% rule[3] applied. Where the data has been suppressed additional suppressions, called masks, have been used making it impossible to calculate the suppressed cells.

Data not already in public domain

Subject to meeting other data security and legal requirements, it can be possible to release trade statistics data that is not already in the public domain, in other words, that which is not routinely already published or made available as part of the OTS or RTS.  In such instances, active confidentiality will be applied to all such requests.

Publicity

Whenever a new suppression is granted on a commodity code, the updated list of applied suppressions is published on the Trade Statistics website; www.uktradeinfo.com. The link to the current list of applied suppressions can be found under Section 6 of this document - ‘Further Information’.

Review of Suppressions

Commercial and Strategic suppressions are reviewed every year.

For suppressions that remain justified, businesses are contacted and asked to confirm if they still require the suppression in place.

If the suppression is no longer required by the business it will be lifted.

If suppressions are still required, businesses must confirm this within 3 weeks of being contacted. They will then be given a suppression at the most suitable level, regardless of whether this increases or decreases the level of disclosivity.

Where the suppression is no longer justified the relevant business is advised by HMRC, and the suppression lifted.

When a strategic suppression is no longer required, it is possible that lifting the suppression may reveal sensitive details of a business’ activity.  Therefore before a strategic suppression is lifted, we will contact such businesses and give them the opportunity to request a commercial suppression before the data is published.

Changes in Combined Nomenclature

The Combined Nomenclature (CN) is updated on an annual basis in order to reflect current commodity code usage and requests to modify existing descriptions.  All suppressions that existed on the commodity codes affected by updates to the CN, are applied to any new and directly related commodity codes that are created.

Where a commodity code (which is currently suppressed) merges into one or more new codes, the resultant codes automatically become suppressed. However, a review is carried out on these affected codes as soon as possible in order to establish whether the suppression needs to remain.

Governance

This policy is designed to meet the recommendations for the Passive confidentiality outlined by the UN International Merchandise Trade Statistics (IMTS) Concepts and Definitions.

It also adheres to the UK Statistics Authority’s Code of Practice for Official Statistics.

Further information

Currently applied suppressions

If you require any further details concerning suppressions please contact:

uktradeinfo Customer Services  

Tel 03000 594 250

email: uktradeinfo@hmrc.gov.uk

Footnotes

[1] The Combined Nomenclature (CN) classifies goods to an 8-digit number, termed the commodity code.

[2] The four suites being non-EU imports, non-EU exports, EU imports and EU exports.

[3] The p% rule states that no contributor to a cell in a table should be estimable to within p% of its original value.