Infrastructure in the UK, investment and net stocks QMI

• Statistical designation: official statistics in development

• Frequency: annual

• How compiled: based on multiple Office for National Statistics (ONS) data sources and other government department data (see Section 3: Important points)

• Geographic coverage: UK and GB

• Related publications: Infrastructure in the UK, investment and net stocks article

This quality and methodology information report contains information on the data's quality characteristics (including the European Statistical System's five dimensions of quality), and the methods used.

The information in this report will help you to:

• understand the strengths and limitations of the data

• learn about existing uses and users of the data

• understand the methods used to create the data

• help you to decide suitable uses for the data

• reduce the risk of misusing data

• "Infrastructure" is widely regarded to mean the basic physical and organisational structures and facilities necessary for an economy, households and businesses to function.

• As such, infrastructure plays a crucial role in the economy and is widely considered an important determinant of productivity and therefore, economic growth; however, there is no formal definition for infrastructure in international statistical manuals.

• Within our publication we follow a data-led, functional definition, focusing on making use of the data available for what is considered core economic infrastructure in the following infrastructure categories: transport, energy, water and waste handling assets, telecommunications, mining and quarrying, and "other" (which includes all industries not in these groups).

• Housing and social infrastructure are not included within our estimates.

• The publication presents three approaches to infrastructure – new work and repair and maintenance construction, government investment and market sector investment and net stocks.

• Our infrastructure estimates are created using several data sources: gross fixed capital formation (GFCF), capital stocks, construction statistics and government annual expenditure tables.

Overview

The Infrastructure in the UK, investment and net stocks article is an official statistic in development publication and is an annual release. The publication uses several official data sources discussed in Section 6: Methods used to produce the data.

Uses and users

Infrastructure plays a crucial role in the economy and is widely considered an important determinant of productivity and therefore, economic growth. It can also enable access to opportunities and improve quality of life.

As discussed in our Developing new measures of infrastructure investment: July 2017 article, improvements in infrastructure are thought to "increase productivity through reducing the costs of production, reducing barriers to trade, increasing competition through opening up markets and widening the pool of labour from which firms can choose. Conversely, the weakening of an economy's infrastructure is likely to have a negative impact on productivity: raising the costs of production, reducing the efficiency of trading relationships and limiting market access."

Given the lack of a formal definition for infrastructure in international manuals, the UK's Office for National Statistics (ONS) follows a data-driven, practical definition.

Despite infrastructure as a concept being relevant to the general public, this publication is produced mainly for topic experts such as the National Infrastructure Commission (NIC) and National Highways, alongside academics.

These data also allow us to be involved in international discussions to produce a fixed definition and set of methods. We have presented at domestic and international conferences and to other countries to support the development of infrastructure statistics.

We are also using our data to further develop the narrow definition and scope of measurement currently used. This is used to develop ad hoc articles such as our Investment in flood defences article and our Redefining digital infrastructure in the UK article.

Strengths and limitations

Strengths

The first strength of the statistics in our infrastructure bulletin and accompanying dataset is that the calculation methodology and data categorisation are consistent across our series of publications on the subject, following the same functional definitions. We are also consistent with the following official data sources:

• our Construction output in Great Britain bulletin

• our General government annual expenditure dataset

• our Local government annual expenditure dataset

• our Business Investment bulletin

Within our Infrastructure in the UK, investment and net stocks: July 2024 article, for the first time, we included revisions to previous years, representing the most accurate data available and ensuring we are consistent over time.

We report constant price estimates, taking out the impact of price inflation to reflect changes in the volume of infrastructure. The prices have a base year of 2021. Our constant price estimates use the latest deflators available from ONS' Capital Stocks team, ensuring consistency with their treatment of price growth when reporting the value of non-financial assets used in the production of goods or services within the UK economy. Read more about deflators in our Deflators and how we use them in economic estimates methodology.

Limitations

Measuring infrastructure comes with numerous challenges. The main conceptual issue is the lack of a universally accepted definition of infrastructure. Neither the System of National Accounts (2008) nor the European System of National and Regional Accounts (ESA 2010) contains a definition. Therefore, we predominantly focus on making use of the data available for what is considered core economic infrastructure for the following infrastructure categories:

• transport

• energy

• water and waste-handling assets

• telecommunications

• mining and quarrying

• "other" (includes all industries not in these categories)

Housing and social infrastructure (such as education or health) is not included, although there may be scope to extend our definition in future editions.

Scarcity of available data is another challenge. For government data, there is a lag between the latest data available and the current period, preventing us from bringing the data any further forward than 2022 in our UK, investment and net stocks: July 2024 article.

Related to data scarcity, the complexities around identifying economic ownership of infrastructure assets makes it difficult for us to produce robust regional estimates. The regional capital team has produced experimental estimates of regional "other structures" using Barbour ABI data. For more information on this, please refer to the Experimental regional gross fixed capital formation estimates by asset type article. However, the modelling used to determine economic ownership of the infrastructure asset (in the absence of available data at the level required) does not always yield realistic estimates.

A further challenge is identifying suitable price indices to produce the constant prices data time series for government investment and construction findings. As most infrastructure assets are long-term investments and therefore, not repeatedly sold or constructed, it is hard to establish a price index time series. Constant prices for market sector net stocks and investment are derived from our capital stocks dataset, according to the methodology outlined in our Chain-linking methods used within the UK National Accounts methodology.

A final limitation is the lack of mechanisms that monitor performance of infrastructure (for better asset life estimates).

Note that all calculations in this bulletin are based on underlying, unrounded data.

Recent improvements

In our most recent release (our Infrastructure in the UK, investment and net stocks: July 2024 article), we were able to publish two years' worth of data for both Market Sector investment and Construction statistics, making our data timelier. For market sector estimates, we also aligned our constant price production with the latest available capital stocks data as of July 2024, therefore using 2021 deflators. This meant that our deflation methods reflect changes in the composition of the economy for the first time following the coronavirus (COVID-19) pandemic. Before this, we at the ONS had suspended rebasing during the pandemic in line with international best practice.

However, we are unable to bring government investment in line with this timetable as government sector annual expenditure tables are published to a slower timetable to meet international deadlines.

Relevance

Infrastructure plays a crucial role in the economy and is widely considered an important determinant of productivity and therefore, economic growth. It can also enable access to opportunities and improve quality of life.

Our publication meets current user needs regarding coverage and content. However, we are continuously looking to improve our estimates in many ways. Firstly, we are looking to expand our definition by publishing a series of ad hoc articles that explore types of infrastructure outside of the functional definition. As we explore further types of infrastructure and expand the remit of measurement for our current types, we hope to develop a broader measure of infrastructure to underpin our lead estimates. This is in line with a growing international view that the list of assets in the scope of infrastructure may be wider than previously thought.

We are also looking to engage in wider economic discussions on infrastructure such as critical minerals, net zero and transport. If you have any interest in this topic, please contact nfa-development@ons.gov.uk.

Accuracy and reliability

Given the lack of a formal definition for infrastructure in international manuals, we at the Office for National Statistics (ONS) follow a data-driven, functional definition.

Joe Grice's article, National accounting for infrastructure, discussed the potential of UK National Accounts and other data sources for measuring infrastructure assets. While noting that there is no internationally agreed definition of "infrastructure", Grice explained that National Accounts information "can be used to construct time series estimates for the infrastructure on a commonsense view of its coverage" to create both stock and flow measures of infrastructure.

The National Infrastructure Commission (NIC) provides expert advice on major long-term infrastructure challenges on economic infrastructure. Infrastructure is referred to as "the basic physical and organisational structures and facilities (for example, buildings, roads, power supplies) needed for the operation of a society or enterprise." We at the ONS have used this functional understanding to define types of economic infrastructure and to inform how we report on it in our publications. Our economic infrastructure categories also align with the NIC's advice. In our Developing new measures of infrastructure investment: July 2017 article, we published findings on this topic from our literature review.

For infrastructure to be acknowledged in the National Accounts (NA) and therefore reported internationally within a harmonised framework, it will have to be in a formal international statistics manual. This is not expected within the next System of National Accounts (SNA2025); however, we will continue to monitor international best practice on defining infrastructure and will revisit our methods accordingly.

Our data are subject to revisions in line with our data providers including when they update their definitions and estimation methods. Reasoning for each iteration of revisions can be found in our bulletins.

Coherence and comparability

We are consistent with several of our data providers.

Our government sector estimates are consistent with:

• our General government annual expenditure: ESA Table 11 dataset

• our Local government annual expenditure: ESA Table 11 dataset

Our construction estimates are consistent with:

• our Construction output in Great Britain: February 2024 bulletin

• our Output in the construction industry: subnational and subsector dataset

Our Market Sector estimates are consistent with:

• our Business investment in the UK: April to June 2024 revised results bulletin

• our Preliminary capital stocks and fixed capital consumption dataset

The data are consistent and provide comparability over time, as we revise in line with our data providers.

We are leading internationally on the topic and collaborate with other countries to further develop the measurement of infrastructure. Organisations such as the NIC have data on comparable topics such as transport and energy. However, they use different methods to measure investment in infrastructure.

Other topic experts who analyse infrastructure include:

• the Infrastructure Project Authority, who analyse investment infrastructure in their Analysis of the National Infrastructure and Construction Pipeline 2023 policy paper

• the Building Cost Information Services (BCIS) who also forecast investment in new work infrastructure

Accessibility and clarity

Our Infrastructure in the UK bulletins are published for free on our website in line with the Code of Practice for statistics. Our recommended format for accessible content is a combination of HTML web pages for narrative, charts, and graphs, with data being provided in usable formats such as CSV and Excel file types. We also offer users the option to download the narrative in PDF format. In some instances, other software may be used or may be available on request.

For information regarding conditions of access to data, please refer to:

• our terms and conditions webpage

• our accessibility statement webpage

Users should be aware that clarity of messaging in this topic area can be affected by:

• the complexity of definitions used

• lack of formal definitions

• complex measures

Timeliness and punctuality

We have made our statistics on construction and the market sector in our publication timelier. Our most recent publication added two new years to the estimates published in our Infrastructure in the UK, investment and net stocks: July 2024 article.

However, we are unable to bring government investment in line with government annual expenditure tables because their publication timetable is a legacy commitment to deliver data to Eurostat. This timeline was established to meet the requirements of the ESA Transmission Programme of Data for the delivery of data on government expenditure by function.

For more details on related releases, our release calendar provides 12 months' advance notice of release dates. In the unlikely event of a change to the pre-announced release schedule, public attention will be drawn to the change and the reasons for the change explained at the same time, as set out in the Code of Practice for Statistics.

Concepts and definitions

Infrastructure assets

Infrastructure assets are considered a subset of fixed capital assets, which have an economic life of over one year. Within our publication, we follow a data-led, functional definition. We focus on making use of the data available for what is considered core economic infrastructure in the following infrastructure categories:

• transport

• energy

• water and waste handling assets

• telecommunications

• mining and quarrying

• "other" (includes all industries not in these groups)

Central, local, and general government

As shown in Eurostat's glossary, Central government (CG), consists of all administrative departments of the state and other central agencies whose responsibilities cover the whole economic territory of a country.

Also defined by Eurostat, Local government (LG) consists of all types of public administration whose responsibility covers only a local part of the economic territory, apart from local agencies of social security funds.

For the UK, general government (GG) is the sum of central and local government.

Net stocks

Net stock is the gross capital stock (defined as the value of all fixed assets still in use at a point in time), less the consumption of fixed capital accrued up to that point. Net stock considers the depreciation of assets over time because of physical deterioration, foreseeable obsolescence, or normal accidental damage.

Market sector

In our publication, to create our estimates for the market sector, we exclude any data relating to the central government, local government and non-profit institutions serving households (NPISH) sectors from our whole-economy estimates. In practice, this means that most of the data relating to industries 84 to 88 are not included in our market sector estimates, with smaller exclusions in other industries where these sectors appear. Data representing government sector investment are presented in our "government investment" tables.

Note that our market sector definition is different to the standard ONS definition of the market sector, which states that any unit selling at an economically significant price is operating in the market.

We present our market sector estimates across seven industry groups, in line with our Developing new statistics of infrastructure: August 2018 article.

These industry groups are:

• energy (division 35, UK Standard Industrial Classification)

• mining and quarrying (divisions 05 to 09)

• water supply (division 36)

• sewerage and waste (divisions 37 to 39)

• warehousing and support activities for transportation (division 52)

• telecommunications (division 61)

• "other", representing the remaining divisions

Infrastructure investment by government

Government infrastructure investment is measured by using government expenditure broken down by function for the following functions of government:

• transport

• communication

• waste management

• waste water management

• water supply

• street lighting

"Other structures" assets

"Other structures" covers structures other than residential structures, including the costs of the streets, sewers and site clearance and preparation.

Examples include:

• highways – streets, roads, railways, and airfield runways

• bridges – elevated highways, tunnels, and subways

• waterways – harbours, dams, and other waterworks

• long-distance pipelines – communication, and power lines

• local pipelines and cables – ancillary works

• constructions for mining and manufacture

• constructions for sport and recreation

Geography

Government and market sector estimates are both for the United Kingdom. Construction statistics only cover Great Britain. Construction statistics have a further regional breakdown included.

Why you can trust our data

The ONS is the UK's largest independent producer of statistics and its national statistical institute. We treat the data that we hold with respect, keeping them secure and confidential, and we use statistical methods that are professional, ethical, and transparent.

Government investment

The sources used within this section of the release are:

• our Central government annual expenditure ESA Table 11 dataset

• our Local government annual expenditure: ESA Table 11 dataset

• our General government annual expenditure: ESA Table 11 dataset

Central government (CG) subsector data are collected from government departments by HM Treasury (HMT). Since 2009 to 2010, the information has been collected according to International Financial Reporting Standards (IFRS), with further breakdowns required for monitoring departmental budgets and for compiling national accounts. Departmental annual accounts, ESA2010 transactions, and Classification of the Functions of Government (COFOG) detail, are all derived from the same dataset. Office for National Statistics (ONS) processes the data and checks quality and consistency with ESA 2010 standards.

CG expenditure is broken into several thousand different programmes and in the main these are at a low enough level to assign to COFOG category at the sub-division level.

Local government (LG) subsector data are collected and published by the government departments responsible for the respective territories:

• England – the Ministry for Housing, Communities and Local Government

• Scotland – the Scottish Government

• Wales – the Welsh Government

The Northern Ireland Executive reports directly to HMT.

Data supplied are detailed expenditure on services provided by local authorities. Data are collected for several policy and accounting purposes. It is allocated to COFOG Level 2 categories by the ONS, which is responsible for ensuring that the local government data can be converted to the ESA 2010 standards.

For LG, most expenditure is classified by the supplier according to the type of service provided. These generally fit well with the COFOG categories.

Within each separate ESA table (Central, Local and General), P5 Capital Formation for each of the following Classification of the functions of government (COFOG) codes extracted as these map closely to our core economic infrastructure categories:

• GF0405 Transport

• GF0406 Communication

• GF0501 Waste Management

• GF0502 Wastewater Management

• GF0603 Water Supply

• GF0604 Street Lighting

Within our Infrastructure in the UK, investment and net stocks article we also use the category "other"; we sum the values of each of the above, minus transport. This is the sum of GF0406, GF0501, GF0502, GF0603 and GF0604. Datasets are available for CG, LG, and GG separately.

Please note that "total CG, LG, GG investment" figures represent total levels of government investment for the whole economy, rather than specifically for infrastructure.

Construction infrastructure by subsector

The sources for this section of the release are Output in the construction industry: sub-national and sub-sector and Output in the construction industry. Data are sourced from the Monthly Business Survey for Construction (also known as the Construction Output Survey) and Value Added Tax (VAT) returns, which collect value of work broken down by type of work from businesses in the construction industry within Great Britain. To obtain subsector data, we at the ONS have developed a new model to apportion construction output more accurately by region and subsector, using new orders data from both the ONS and Barbour ABI. For more information, please refer to our Construction output QMI.

Within this dataset, from Table 1, Construction output, we extract: value, non-seasonally adjusted, current prices by type of work, £ million.

Within the sector "Infrastructure", we take data for each of the following infrastructure subsectors (shown along with their dataset identifier code):

• water (MV73)

• sewerage (MV74)

• electricity (MV75)

• roads (MV76)

• railways (MV77)

• harbours (MV78)

• other (MV79)

"Other" consists of the gas, communications, and air transport subsectors.

For "total infrastructure" we use dataset identifier code MV6N. Similarly, the "of which public/ private" figures are taken from Table 1, (codes MV7A and MV7B, respectively). Data are available per quarter of each year. We therefore sum the value of year quarter within a year to reach an annual figure.

The "total repair and maintenance" figures are from Table 4a, Construction output in Great Britain, value, seasonally adjusted, current prices, by sector, from our Output in the construction industry dataset. Specifically, we use the annual figures for, repair and maintenance or "R&M Infrastructure" (code N42T).

Construction by region

The source for this section is our Output in the construction industry: subnational and subsector dataset. To obtain subnational data, we at the ONS have developed a new model to more accurately apportion construction output by region and subsector, using new orders data from both the ONS and Barbour ABI and applying this to our Construction output in Great Britain dataset. For more information, please refer to our Construction output QMI and our Construction development: improvements to regional and subsector level estimates, June 2018 article.

Within this dataset, from Table 2, Construction output, we extract value, non-seasonally adjusted, current prices, by region, £ million. For each separate country or region of England, we take information for infrastructure (new work) from the "infrastructure" category, dataset identifier code MV8F, and the total from "all new work" category, (code MV8J).

For infrastructure repair and maintenance figures (R&M), we take "infrastructure R&M", (code MV8N), with total repair and maintenance taken from "all R&M", (code MV8O).

For infrastructure's share of total construction (%), we divide "infrastructure" by "all new work", and for infrastructure R&M's share of total R&M (%), we divide "infrastructure R&M" by "All R&M".

Data are available per quarter of each year. We therefore sum the value of each quarter within a year to reach an annual figure.

These are the dataset identifier codes for each country of Great Britain and region of England:

North East

Infrastructure: MV8F

All new work: MV8J

Infrastructure repair and maintenance: MV8N

All repair and maintenance:MV8O

North West

Infrastructure: MVH4

All new work: MVH8

Infrastructure repair and maintenance: MVI4

All repair and maintenance:MVI5

Yorkshire and the Humber

Infrastructure: MV8S

All new work: MV8W

Infrastructure repair and maintenance: MV92

All repair and maintenance:MV93

East Midlands

Infrastructure: MV97

All new work: MV9B

Infrastructure repair and maintenance: MV9F

All repair and maintenance:MV9G

West Midlands

Infrastructure: MVF9

All new work: MVG4

Infrastructure repair and maintenance: MVG8

All repair and maintenance:MVG9

East

Infrastructure: MV9K

All new work: MV9O

Infrastructure repair and maintenance: MV9S

All repair and maintenance:MV9T

London

Infrastructure: MV9K

All new work: MV9O

Infrastructure repair and maintenance: MV9S

All repair and maintenance:MV9T

South East

Infrastructure: MVB4

All new work: MVB8

Infrastructure repair and maintenance: MVC3

All repair and maintenance:MVC4

South West

Infrastructure: MVC8

All new work: MVD4

Infrastructure repair and maintenance: MVD8

All repair and maintenance:MVD9

Wales

Infrastructure: MVE4

All new work: MVE8

Infrastructure repair and maintenance: MVF4

All repair and maintenance:MVF5

Scotland

Infrastructure: MVI9

All new work: MVJ4

Infrastructure repair and maintenance: MVJ8

All repair and maintenance:MVJ9

For infrastructure's share of total construction (%), we divide "infrastructure" by "all new work" for each territory and for infrastructure R&M's share of total R&M (%), we divide "infrastructure R&M" by "all R&M" for each.

All data are available per quarter of each year. We therefore sum the value of each quarter within a year to reach an annual figure.

Market sector investment

The source used in this section is an unpublished version of a Gross Fixed Capital Formation (GFCF) dataset, which is consistent with our Business Investment dataset. Business investment estimates are based primarily on the results of the Quarterly Acquisitions and Disposals of Capital Assets Survey (QCAS), which collects data from UK businesses for the private sector, and those for the government sector include the online system of central accounting and reporting (OSCAR). For more information, please refer to our Business Investment QMI. 

Since its inception, market sector infrastructure in the UK has been captured within the "other structures" asset class of GFCF. Published estimates of GFCF do not break down estimates of "other buildings and structures" into "other buildings," "other structures" and "land improvements." Instead, since 2019, the expenditure on "other structures" has been separated from the asset "other buildings and structures" by using data from the Annual Acquisitions and Disposals of Capital Assets Survey (ACAS) in line with our methods for the breakdown of capital stocks.

"Other structures" estimates are broken down into six categories, where the flow of services or benefits accrues to multiple industries and sectors beyond the industry or sector possessing the asset:

• transport other than roads

• energy

• water, flood control and waste management

• communications

• roads

• other publicly owned infrastructure not elsewhere included

In our production process, we filter the other structures data for each industry group. For example, for mining and quarrying, we filter to show industries, 5, 6, 8 and 9. The industries used for each published industry group are shown in Table 1.

All data are available per quarter of each year. We therefore sum the value of each quarter within a year to reach an annual figure.

We then calculate constant price (KP) data using deflators, which are provided to us by the Capital Stocks team. These are currently on a "base year 2021 equals 100" basis.

Market sector net stocks

The source used in this section is an unpublished version of a Capital Stocks dataset, which is consistent with our Preliminary capital stocks and fixed capital consumption dataset. In turn, the main data source for estimating capital stocks data series is GFCF, see Section 6: Methods used to produce the data, under the subheading "Market sector investment", for further details. GFCF measures acquisitions minus disposals of fixed assets (produced assets that are used repeatedly or continuously in production processes for more than a year) and costs associated with the ownership transfer of these fixed assets. Capital stocks estimates are then calculated using the Perpetual Inventory Method (PIM). This involves cumulating GFCF across time and accounting for retirement and depreciation. The asset life data for "other structures" being predominantly taken from company accounts because most of the assets of this type are owned by a small number of large enterprises operating in specific services and utilities industries, such as mining and quarrying, water and sewerage, and telecommunications services.

For more information, please refer to our Capital stocks and fixed capital consumption QMI. 

To create the market sector net stocks dataset, we use both current price and constant price data for the category "other structures" only. See Section 6: Methods used to produce the data, under the subheading "Market sector investment", for further details on "other structures".

We then filter "other structures" for each industry group. For example, for mining and quarrying, we filter to show industries, 5, 6, 8 and 9.

Please refer to the industry list under "Market sector investment" for our full industry groupings.

To calculate annual figures, we take only the value for October to December, Quarter 4 (Q4), for the relevant year in line with the balance sheet approach to reporting annual data, that is, the value for 1997 is the same as the value for Q4 1997.

The total of all investment and stocks is calculated as the sum of all industry groupings within a given year.

Main data sources

• Business Investment

• Capital Stocks

• Construction Statistics

• General government ESA table 11

• Local government ESA table 11

How we analyse and interpret the data

We produce time series analysis to show how investment in infrastructure assets changes over time. We also provide industry breakdowns.

To ensure we are using the data provided to us correctly, we consult with our data providers to explain how we are interpreting their data and to highlight any important messages.

Within our publication, we also try to provide economic context for any data changes to allow for better understanding.

How we quality assure and validate the data

Rigorous quality assurance is carried out at all stages of production. Specific procedures include:

• scrutinising input data to investigate the accuracy of any abnormal values

• scrutinising trends in the totals, assets, regions, and industry breakdowns

• comparing current estimates with previous estimates to see where substantial changes are taking place, and to understand the reasons for those changes

• completing revisions analyses on our input data using PowerBI

• having individuals external to the team (either within other teams or data providers) check the dataset

• checking output tables to ensure that there are no errors or inaccuracies during the creation of published tables

How we disseminate the data

Infrastructure data are disseminated primarily through publication of statistical bulletins and ad hoc releases on the ONS website. The publication schedule is detailed in Section 5: Quality characteristics of the data, under the subheading "Timeliness and punctuality". The Intangibles and Infrastructure team publishes regular statistical bulletins, with releases increasingly promoted through ONS social media accounts.

Internal stakeholders and data suppliers receive data ahead of release as part of the quality assurance process.

We invite users to contact us at nfa-development@ons.gov.uk with questions or comments on our development work, estimates, or future plans.