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Understanding Industries & Sectors


Since 1948, Standard Industrial Classifications, or SIC codes, have provided a framework for the collection, tabulation, presentation and analysis of statistical data relating to industrial structure in the UK.

Industries versus Sectors

The UK SIC is based on a series of 21 letters (A-U) denoting sections of the economy, each of which are further broken down into increasingly specific activities based on a hierarchical 5-digit system; 2-digits for divisions, 3-digits for groups, 4-digits for classes, and in several cases 5-digits for subclasses.

An analysis of industry sections is the commonly used approach to gain a basic understanding of an economy’s industrial structure and you will find separate pages on this website for industry output, industry employment and industry productivity.

However, industry sections do not typically correspond with the economic sectors often referred to in public and policy circles (e.g. digital, marine, tourism). Therefore, additional modelling has also been undertaken to produce data for a selection of key sectors based on bespoke combinations of SIC codes.

Defining Sectors

In defining bespoke sectors there are always compromises and/or limitations. It is not straightforward to simply match industry data with local opinions regarding the types of activities a sector is thought to include and differences of opinion typically exist as to what a sector ought to include. Moreover, what we tend to think of as sectors are rarely, if ever, discrete systems of economic activity; there tend to be cross-overs in activity between sectors and supply chains are often complex and sprawling.

However, it is possible to capture a ‘best-fit’ between national statistical data and local views pertaining to sectoral composition in a way that adds to our understanding of local sectoral strengths and priorities. The definitions used are not nationally agreed definitions and such rarely exist for the aforementioned reasons. Moreover, they may be subject to small changes in the future as qualitative views on sectoral compositions change, or if more sophisticated modelling assumptions can be developed allowing us better approximate the proportional contribution of particular activities to a given sector (e.g. for those activities which do not fall wholly within a given sector).

Our sectors, listed below, have been defined using agreed combinations of 2, 3, 4 and 5-digit SIC codes. 

  • Advanced Engineering and Manufacturing (AEM)
  • Aerospace
  • Marine
  • Food & Drink
  • Defence
  • Environmental Industries
  • Digital Technologies
  • Agritech Industries
  • Tourist Industries
  • Photonics & Electronics

Many of these sectors are of key importance specifically to Somerset, either because they represent competitive strengths (e.g. advanced engineering and manufacturing, food and drink, defence), and/or because they represent significant growth opportunities for the future (e.g. digital, agritech).