Index of Services, UK: April 2016

Monthly movements in output for the services industries: distribution, hotels and restaurants; transport, storage and communication; business services and finance; and government and other services.

This is not the latest release. View latest release

29 November 2016

Following a quality review, a processing error has been identified in the compilation of the estimates for the rail transport industry (49.1-2), which affects the period Quarter 1 1997 to Quarter 2 2016. In line with the National Accounts revision policy, this error will be corrected in the Index of Services and Quarterly National Accounts due for publication on 23rd December 2016 for data from Quarter 1 2015 and in the Blue Book 2017 consistent releases for data prior to this period. The average impact over this period on quarter-on-quarter Index of Services and GDP growth is 0.00%. This processing error does not impact quarter on quarter growth into Quarter 3 2016.

This is an accredited national statistic.

Contact:
Email Robert Smith

Release date:
30 June 2016

Next release:
27 July 2016

1. Main points

The Index of Services is estimated to have increased by 3.0% in April 2016 compared with April 2015. All of the 4 main components of the services industries increased in the most recent month compared with the same month a year ago.

The largest contribution to total growth came from business services and finance, which contributed 1.2 percentage points.

The latest Index of Services estimates show that output increased by 0.6% between March 2016 and April 2016. This follows negative growth of 0.3% between February 2016 and March 2016, which is revised down 0.2 percentage points from the previous estimate.

The Index of Services increased by 0.6% in Quarter 1 (Jan to Mar) 2016 compared with Quarter 4 (Oct to Dec) 2015. This figure was unrevised from the estimate used in the gross domestic product (GDP) second estimate, published on 26 May 2016. This figure is consistent with the Quarterly National Accounts, published on 30 June 2016.

In this release of data, the earliest period open to revision is January 1997 as this dataset contains the annual updates which will be included in the Blue Book 2016 dataset; more information is included in the revisions section. The reference year and last base year for the index have been moved to 2013. The figures within this release are estimates and are on a seasonally adjusted basis.

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2. Understanding the Index of Services (IoS)

About the IoS

The monthly IoS provides a timely indicator of growth in the output of the services industries. The IoS is an important economic indicator and shares exactly the same industry coverage as the corresponding quarterly series within UK gross domestic product (GDP). The primary purpose of the IoS is to produce a short-term measure of the output of the services industries within the UK economy and show the monthly movements in the gross value added (GVA) of the services industries (2007 Standard Industrial Classification (SIC 2007) sections G to T).

The 4 main components of the services industries are:

  • distribution, hotels and restaurants
  • transport, storage and communications
  • business services and finance
  • government and other services

The IoS is the largest contributor to the output approach to the measurement of GDP, accounting for 78.8% of UK GDP in 2013.

All data in this bulletin are seasonally adjusted estimates and have had the effect of price changes removed (in other words, the data are deflated). Further information on some of the main concepts (including seasonal adjustment and deflation) underlying the estimates can be found in background note 12.

The quality of the IoS

The IoS is published around 8 weeks after the end of the reference month. There is no simple way of measuring the accuracy of the IoS, that is, the extent to which the estimate measures the underlying “true” value of the output growth (of the services industries) in the UK for a particular period. All estimates, by definition, are subject to statistical uncertainty and for many well-established statistics the Office for National Statistics (ONS) measures and publishes the sampling error associated with the estimate, using this as an indicator of accuracy. However, as IoS is constructed from a wide variety of data sources, some of which are not based on random samples, we don’t publish a measure of the sampling error associated with it.

Reliability is one dimension of measuring accuracy, using evidence from analyses of revisions to assess the closeness of early estimates to subsequent estimated values. Revisions are an inevitable consequence of the trade-off between timeliness and accuracy. Figures for the most recent months are provisional and subject to revision in light of:

  • late responses to surveys and administrative sources
  • forecasts being replaced by actual data
  • revisions to seasonal adjustment factors, which are re-estimated every month and reviewed annually

Revisions to the IoS are typically small (around 0.1 to 0.2 percentage points), with the frequency of upward and downward revisions broadly equal. More information on the most recent revisions analysis can be found in the component analysis section and in background note 18.

It should be noted that care should be taken when using the month-on-month growth rates, due to their volatility (background note 11).

Further information on the quality of the IoS is available in the Quality of the IoS report on the Index of Services methodology page on our website. It should be noted that as part of the IoS industry review process, we are continually working on methodological changes to improve the accuracy of the IoS.

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3. Main information

The Index of Services (IoS) measures the quantity of output from all UK services industries, which account for more than three-quarters of the output approach to the measurement of GDP. Index values are currently referenced to 2013 so that the average for 2013 is equal to 100. Therefore, an index value of 110 would indicate that output is 10% higher than the average for 2013.

As seen in Figure 1, the IoS increased by 3.0% in April 2016 compared with April 2015. In order of their contribution to growth (listed in Table IOS1 in the Index of Services publication tables dataset):

  • business services and finance increased by 3.1%
  • distribution, hotels and restaurants increased by 5.0%
  • transport, storage and communications increased by 3.7%
  • government and other services increased by 1.1%

Further detail on these movements can be found in the component analysis section.

Between March 2016 and April 2016, as seen in Figure 2, IoS output increased by 0.6%.

Out of the 4 main components of the services industries, 3 increased in the most recent month compared with the previous month. In order of their contribution to growth (listed in Table IOS1 in the Index of Services publication tables dataset):

  • transport storage and communication increased by 2.1%
  • business services and finance increased by 0.6%
  • distribution, hotels and restaurants increased by 0.8%

In contrast, government and other services decreased by 0.1%.

More detail on individual components can be found in the Index of Services publication tables dataset. The tables also provide information on the growth for the 3 months ending in April 2016 compared with the previous 3 months and compared with the 3 months ending April 2015.

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4. Economic background

Total services grew by 2.5% between Quarter 1 (Jan to Mar) 2015 and Quarter 1 (Jan to Mar) 2016 and by 0.6% between Quarter 4 (Oct to Dec) 2015 and Quarter 1 (Jan to Mar) 2016. This compares with growth rates of 2.0% and 0.4% respectively for the economy as a whole.

Since 1997, the services industries as a whole have grown at a faster rate than all other headline industries. While gross domestic products (GDP) has grown at a compound average growth rate (further information on compound average growth can be found in background note 12) of 2.0% per year from 1998 to 2015, services have grown at a compound average growth rate of 2.6% per year. (More information can be found in Quarterly national accounts: January to March 2016. This has led to a continuing re-orientation of the economy towards services, despite productivity in the services industries as a whole rising more slowly than in the production industries (and manufacturing in particular) since 1997 (more information can be found in Labour Productivity: Oct to Dec 2015). The higher output growth therefore reflects the increasing share of the labour force employed in services, which grew from 73% to 80% between 1997 and 2015 (UK Labour Market: June 2016).

In addition to strong long-run growth, the services industries as a whole were also less affected by the downturn (between 2007 and 2009) than other headline industries, such as production and construction. Following the downturn, the relatively strong growth in the services industries has provided the largest contribution to the recovery and has been the only headline industry grouping to have surpassed its pre-downturn peak levels (more information can be found in Quarterly national accounts: January to March 2016).

Even though the services industries as a whole have been performing better than all other headline industries, the growth within the services’ sub-components has been quite varied. Figure 3 shows that from 1998 to 2015, transport, storage and communication and business services and finance grew faster than the services industries as a whole, at compound average growth rates of 4.0% and 3.2% per year respectively. Meanwhile, services grew at a compound average growth rate of 2.6% per year over the same period. However, government and other services, and distribution, hotels and restaurants grew at slower rates than the services industries as a whole (at compound average growth rates of 1.5% and 1.9% per year respectively) from 1998 to 2015.

The economy’s downturn, Quarter 1 (Jan to Mar) 2008 to Quarter 2 (Apr to June) 2009, affected the 4 sub-components of the services industries to different degrees. Distribution, hotels and restaurants, and transport, storage and communication were affected the most with their output falling by 9.4% and 9.3% respectively, while the output of the services industries as a whole contracted by 4.6% over the same period. Business services and finance, and government and other services were impacted less severely, with their output contracting by 3.9% and 0.3% respectively.

Business services and finance experienced a strong recovery following the economy’s downturn and in Quarter 1 (Jan to Mar) 2016, output was 13.2% above pre-downturn levels. The recoveries of transport, storage and communication, and distribution, hotels and restaurants were also strong and in Quarter 1 (Jan to Mar) 2016 output was 11.5% and 11.7% above their respective levels in Quarter 1 (Jan to Mar) 2008. However, the recovery of the government and other services industries was more modest and in Quarter 1 (Jan to Mar) 2016, output was 6.4% above its Quarter 1 (Jan to Mar) 2008 value.

Figure 4 shows the share of nominal (unadjusted for the effect of price changes) gross value added (GVA) accounted for by services in the UK and a selection of other major economies. More information on data for France, Germany, Italy, Japan and the USA can be found on the Organisation for Economic Co-operation and Development (OECD) website. In 1997, the share of nominal GVA accounted for by services in the UK was just under 72%, in the top half of the range relative to the other economies shown. By 2014 the UK had become relatively more reliant on services, as its share rose to over 79% of nominal GVA.

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5. GDP impact and components

With a weight of 78.8%, the services industries are the largest industrial grouping in the output approach to measuring gross domestic product (GDP). The releases for the short-term economic indicators that feed directly into the output approach to measuring GDP include a table detailing growth in the 4 main industrial groupings (Table 2). This will aid understanding of the relationship between the individual short-term releases and GDP output.

In Quarter 1 (Jan to Mar) 2016, GDP was estimated to have increased by 0.4% compared with the previous quarter. The contribution an industry grouping makes to the GDP quarterly growth is dependent on the quarterly change in that industry grouping and its weight within the output approach to measuring GDP.

Monthly estimates are produced for each industrial grouping except agriculture. The April 2016 estimates for production, construction and retail sales were published on 8 June 2016, 10 June and 16 June 2016 respectively. The Quarterly National Accounts for Quarter 1 (Jan to Mar) 2016 was published on 30 June 2016 alongside this bulletin. In line with the usual Blue Book process estimates of production and construction, used in the Quarterly National Accounts published 30 June 2016, are consistent with the Blue Book 2016 dataset rather than the most recent publications.

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6. Component analysis

Distribution, hotels and restaurants

The index of distribution, hotels and restaurants increased by 5.0% in April 2016 compared with April 2015; this follows an increase of 4.2% in March 2016 compared with the same month a year earlier. The main contributors to the increase were: wholesale and retail trade and repair of motor vehicles and motorcycles, which increased by 14.0%, and retail trade except of motor vehicles and motorcycles, which increased by 4.8%.

Transport, storage and communications

The index of transport, storage and communications increased by 3.7% in April 2016 compared with April 2015; this follows an increase of 1.5% in March 2016 compared with the same month a year earlier. The main contributors to the increase were: computer programming, consultancy and related activities, which increased by 8.9%, and publishing audiovisual and broadcasting activities, which increased by 9.8%.

Business services and finance

The index of business services and finance increased by 3.1% in April 2016 compared with April 2015; this follows an increase of 2.2% in March 2016 compared with the same month a year earlier. The main contributors to the increase were: other professional service activities, which increased by 4.6%, administrative and support service activities, which increased by 4.6%, and other professional scientific and technical activities, which increased by 13.0%.

Government and other services

The index of government and other services increased by 1.1% in April 2016 compared with April 2015; this follows an increase of 1.2% in March 2016 compared with the same month a year earlier. The main contributors to the increase were: human health and social work activities, which increased by 3.7%, and other service activities, which increased by 3.2%.

Revisions

The Index of Services (IoS) follows the National Accounts revisions policy. Revisions are caused by a number of factors including, but not limited to:

  • revisions to source data due to late responses
  • actual data replacing forecast data
  • revisions to seasonal factors that are re-estimated every period

More information on IoS revisions is available on the Index of Services methodology page.

We produce revisions triangles of services growth to provide users with an indication of the reliability of this main indicator. Statistical tests are performed on the average revision to test if it is statistically significantly different to 0. Further information can be found in background note 17.

In this release of data, the earliest period open to revision is January 1997 as this dataset contains the annual updates which will be included in the Blue Book 2016, to be published on 29 July 2016.

There are numerous sources of revision which will affect services in the Blue Book 2016 publication, including but not limited to:

  • updates to the annual gross value added (GVA) weights
  • updated source data including inclusion of the postal and courier services and water transport industry reviews and changes to the measurement of imputed rental
  • improved statistical methods
  • alignment to gross domestic product (GDP) annual growths
  • review of seasonal adjustment models

As is common for the first Index of Services publication following the annual updates, there are more and larger revisions than an ordinary publication. These annual changes include updating the reference year and chain link weights for 2013.

Further information on improvements to the output approach to measuring GDP and revisions can be found in the GDP output improvement report.

Further details on the revisions to the IoS components can be found in the RIOS1 tables in the Index of Services publication tables dataset.

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7. Industry spotlight: Other professional, scientific and technical activities

According to the UK Standard Industrial Classification 2007 (SIC 2007), other professional, scientific and technical activities (industry 74) include the provision of specialised design, photographic and translation and interpretation activities.

In 2015, this industry generated £9.8 billion of output gross value added (GVA) in current prices, which represented 7.9% of the GVA in the professional, scientific and technical activities section (section M). The share of total output attributed to this industry increased slightly between 1997 and 2015 from 0.4% to 0.6%, suggesting that the industry grew slightly faster than the rest of the economy (Quarterly National Accounts: January to March 2016).

Figure 6 shows that other professional, scientific and technical activities has outperformed the services industries, although it has experienced significant volatility. From Quarter 2 (Apr to June) 1997 to Quarter 1 (Jan to Mar) 2008 other professional, scientific and technical activities grew at a compound average growth rate of 0.9% per quarter, the same rate as services as a whole. Further information on compound average growth can be found in background note 12.

During the economy’s downturn between Quarter 1 (Jan to Mar) 2008 and Quarter 2 (Apr to June) 2009, the output of the services industries contracted by 4.6%. Other professional, scientific and technical activities were affected much more severely and over a slightly longer period, falling by 20.4% between Quarter 1 (Jan to Mar) 2008 with its trough in Quarter 3 (July to Sept) 2009.

Services then returned to strong and consistent growth, growing at a compound average growth rate of 0.6% per quarter and surpassing its pre-downturn peak in Quarter 2 (Apr to June) 2012. Despite contracting more than services as a whole in the downturn, other professional, scientific and technical activities saw much faster growth, growing at a compound average growth rate of 2.1% per quarter. By Quarter 1 (Jan to Mar) 2016 the services industries as a whole were 10.7% above their value in Quarter 1 (Jan to Mar) 2008, while other professional, scientific and technical activities was 35.8% above its value.

In the post-downturn period (between 2010 and 2015) the volume of other professional, scientific and technical activities grew by 39.2%, coinciding with a 35.0% increase in the number of employee jobs in the industry. Over the same period, the number of employee jobs worked by men increased by 27.9%, whilst the number of employee jobs worked by women increased by 46.4%. Looking at the working patterns of male and female employees within the industry, male employees were largely made up of full-time workers (86.2% of total male employees in 2015). In contrast there were a greater proportion of female part-time workers within the industry (34.3% of total female employees in 2015) (UK Labour Market: June 2016).

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8 .Background notes

  1. What’s new

    Blue Book 2016

    This release is consistent with the Blue Book 2016 Quarterly National Accounts published on 30 June 2016. As usual, as part of this process, the whole Index of Services time series is open for revision and new gross value added (GVA) weights are included. In addition, the recommendations of the water transport and postal and courier activities industry review have been incorporated. Seasonal adjustment models have also been reviewed in this release. Also in this release the reference year and chain linked weights have been updated to 2013.

  2. Continuous improvement of GDP

    The GDP output improvement report, published on 30 September 2015, provided a detailed update of the implementation of improvements for Blue Book 2015, progress on industry reviews and wider cross-cutting improvements, a comprehensive timetable for the industry review project, and progress on experimental statistics. An updated version of this report is due for publication 1 July 2016.

    To reflect these improvements, along with updated weights, the GDP(O) source catalogue was updated alongside the Blue Book publication on 30 October 2015. An updated version of this catalogue is due for publication 29 July 2016.

    The industry review programme reviews the concepts, methods and data sources underpinning the short-term indicators that support the IoS bulletin. The 2 latest reviews were published on 23 March 2016 and covered the water transport industry and the postal and courier activities industry. The recommendation of these reports are included in this release of data.

  3. Experimental Statistics

    The Index of Services (IoS) achieved National Statistics status in 2007. This was due, at least in part, to a series of industry reviews which underpinned short-term estimates. However, a number of low-level industries remained experimental statistics when the programme of industry reviews paused in 2008 to focus on the transition to Standard Industrial Classification 2007 (SIC2007), improved deflator methodology, and the implementation of a new IT platform.

    In 2011, IoS moved to SIC2007 and a reappraisal of the experimental industries was made using detailed comments from methodologists who quality assured the progress of IoS towards the National Statistics label. This review was published in August 2012 and outlined the 17 industries which remained experimental. A review of the 17 industries has taken place by experts against the Code of Practice for Official Statistics and, in noting the original comments, we are clear that the issues and requirements have been addressed where appropriate. Further details can be found in the latest GDP output improvement report. Agreement has been given by the Director General for Economic Statistics to officially move these Experimental Statistics to Official Statistics.

  4. VAT project update

    An article entitled HMRC VAT update was published on 4 April 2016, the fourth in a series of articles.

    There are 3 previous articles which have been published in this series:

    Feasibility study into the use of HMRC turnover data within Short-term Output Indicators and National Accounts, 14 August 2015.

    Exploitation of HMRC VAT data, 7 October 2015.

    HMRC VAT project update, 21 December 2015.

  5. What do you think?

    As a user of our statistics we welcome your feedback on this publication. If you would like to get in touch please contact us via email: ios.enquiries@ons.gov.uk.

  6. Special events

    We maintain a list of candidate special events in the special events calendar. As explained in our special events policy, it is not possible to separate the effects of special events from other changes in the series.

  7. Understanding the data

    Short guide to the Index of Services

    The Index of Services (IoS) shows the monthly movements in the gross value added (GVA) of the service industries (2007 Standard Industrial Classification (SIC 2007) sections G to T). These industries accounted for around 79% of gross domestic product (GDP) in 2013. The index is estimated using the same data sources and national accounts methodology as the quarterly estimate of services industries’ GVA within the output approach to measuring GDP (GDP (O)). These consist of the distribution, hotels and restaurant industries (SIC 2007 sections G and I), transport, storage and communications (sections H and J), business services and finance (sections K to N), and government and other services (sections O to T).

  8. International comparison

    International comparison with the IoS is difficult, as most comparable economies don’t produce equivalent estimates. Eurostat turnover in services estimates are not comparable with the IoS, as they exclude the wholesale and retail trade; furthermore, most of the estimates are only available quarterly. The USA also produces services output estimates, but only on a quarterly basis, with a 4-month lag time. Japan has a direct equivalent of the IoS, but the estimates are not seasonally adjusted. The closest equivalent estimates are from Canada, which produces a monthly output estimate of GDP with a breakdown by industry (including an aggregate for services). There are also comparable quarterly estimates from Sweden and Ireland.

  9. Short guide to national accounts

    The national accounts provide an integrated description of all economic activity within the economic territory of the UK, including activity involving both domestic units (that is, individuals and institutions resident in the UK) and external units (those resident in other countries). In addition to being comprehensive, the accounts are fully integrated and internally consistent. More information can be found in UK national accounts - a short guide.

  10. How our statistics explain the economy

    The IoS is mentioned in ONS statistics explain the UK economy, which was released on our website on 27 June 2014, alongside Quarterly National Accounts for Quarter 1 (Jan to Mar) 2014.

  11. Interpreting the data

    Some monthly data are volatile. When looking at growth rates, the headline IoS figures focus on the percentage change between the most recent month-on-a-year earlier and the most recent 3 months-on-a-year earlier.

    The monthly Index of Services statistical bulletin is usually published on the same days as the Gross Domestic Product Preliminary Estimate statistical bulletin, the Second Estimate of Gross Domestic Product statistical bulletin or the Quarterly National Accounts statistical bulletin.

    The data for the IoS in this statistical bulletin are generally consistent with the Quarterly National Accounts: Quarter 1 (Jan to Mar) 2016, published on 30 June 2016. However, rounding can sometimes cause differences between the 3-monthly growth rates presented in this release, compared with the quarterly growth rates presented in the Quarterly National Accounts. Data for the retail industry are broadly comparable with the retail sales release, published on 16 June 2016, but as the 2 series operate under different revisions policies, there can be timing differences in the updating of the 2 series. Also, adjustments to the data within the IoS release are sometimes made at the time of the Blue Book to improve the coherence of the 3 approaches to measuring GDP. Therefore, inconsistencies between the 2 series are not unusual but tend to be small. There are also conceptual and coverage differences between retail sales and retail output which can lead to apparent inconsistencies.

  12. Definitions and explanations

    Definitions found within the main statistical bulletin are listed:

    Index number

    An index number is a number which indicates the change in magnitude relative to the magnitude at a specified point, the latter usually taken as 100. The Index of Services (IoS) is currently referenced to 2013 so that the average for 2013 is equal to 100. Therefore, an index value of 110 would indicate that output is 10% higher than the average for 2013.

    Seasonal adjustment

    The index numbers in this statistical bulletin are all seasonally adjusted. This aids interpretation by removing annually recurring fluctuations, for example, due to holidays or other regular seasonal patterns. Unadjusted data are also available.

    Seasonal adjustment removes regular variation from a time series. Regular variation includes effects due to month lengths, different activity near particular events such as shopping activity before Christmas, and regular holidays such as the May bank holiday.

    Some features of the calendar are not regular each year, but are predictable if we have enough data, for example, the number of certain days of the week in a month may have an effect, or the impact of the timing of Easter. As Easter changes between March and April, we can estimate its effect on time series and allocate it between March and April depending on where Easter falls. Estimates of the effect of the day of the week and Easter are used respectively to make trading day and Easter adjustments prior to seasonal adjustment.

    X-13-ARIMA-SEATS is the current seasonal adjustment software used for the IoS.

    Value (current price)

    Economic transactions involve the production of goods and the sale of goods and services (commodities). The monetary value (or current price) of these transactions is a product of the quantity produced or sold and the unit price. In a particular period, the total (aggregate) value of all transactions taking place in the economy is simply the sum of the individual transaction values in that period. The current price is sometimes referred to as the “nominal” price.

    Volume (constant price)

    When it comes to comparing the difference in aggregate values between 2 time periods, the observed movement is generally a combination of changes in quantity and changes in price. In a lot of cases, the interest of users of economic data lies in understanding the degree to which economic growth is being driven by changes in quantities (that is, physical volumes of production and consumption). It is standard practice to present many economic statistics as volume series (showing changes in the level of the series that have not been affected by changes in price) and such series are referred to as “at constant prices” or “real” prices.

    Deflation

    The process of removing price changes from a value series and converting to a volume series is known as deflation. Where information on prices is not available, but value and volume data are, an implied deflator (or price) can be derived by dividing the first by the latter. All index numbers presented in this bulletin are volume measures and have had the effect of price changes removed unless otherwise stated.

    Chained volume measures

    The indices in this bulletin are presented as “chained volume” measures, meaning that successive volume estimates have been linked (or chained) together. Annual chain-linking was introduced in 2003 and is considered preferable to producing standard volume series, as chained volume measures more accurately reflect volume changes over time. More information on chain-linking can be found in the Tuke and Reed (2001) Economic Trends article, and a paper on chain-linking weights in the output approach to measuring GDP can be found on the Methods and sources page.

    Compound average growth

    Compound average growth is the rate at which a series would have increased or decreased if it had grown or fallen at a steady rate over a number of periods. This allows the composition of growth in the recent economic recovery to be compared to the long run average.

    Gross domestic product (GDP)

    The total value of production activity in the economic territory. It is the balancing item on the production account for the whole economy. Domestic product can be measured gross or net of consumption of fixed capital (or depreciation). It is presented in the accounts at market (or purchasers’) prices. A further distinction is that it can be at current prices or chained volume measures.

  13. Methods

    The Index of Services methodology can be found on our website.

  14. Composition of the data

    The IoS uses a wide variety of different data, from many sources, which are produced on either an annual, quarterly or monthly basis.

    Some of the indicators are derived using current price turnover deflated by a suitable price index. This includes data from the monthly business survey (MBS), an ONS short-term survey on different parts of the economy. It is one of the main data sources used in the compilation of the IoS.

    More information on MBS data can be found within the Quality and Methodology Information (QMI) report.

    Other sources use direct volume measures that don’t need to be deflated, such as Civil Aviation Authority data for air transport. Other proxies, such as employment numbers, are also used. This is the case with public sector employment and workforce jobs data.

    Where monthly data are not available (for example, when data are delivered quarterly or annually), monthly estimates are derived by forecasting data. This is done using the X-13-ARIMA-SEATS forecasting method and interpolating a monthly path using a cubic spline.

    An X-13-ARIMA-SEATS forecast is also used where actual data at industry level are not available for the latest period (a lower proportion of actual data are available for the latest month). When the forecast is replaced by actual data, this may lead to revisions to the published data.

    The IoS adheres to the Government Statistical Service disclosure control policy. More information can be found in the Quality and Methodology Information (QMI) report.

  15. Response rates

    Approximately 42% of the IoS estimates are based on data collected via our monthly business survey (MBS). In addition, approximately 7% of the IoS estimates are collected via our retail sales inquiry (RSI). The remainder is based on data received from other ONS sources and external data sources. The MBS and RSI response rates for data included in this publication are presented for the current months and the 3 months prior in Table 4. The response rates for the previous periods are updated to reflect the current level of response, incorporating data from late returns. There are 2 response rates included; the first is a percentage of the sampled turnover returned and the other is a percentage of the amount of questionnaire forms returned.

    Historical MBS response rates for the services industries as at the time of the relevant publication are also available back to 2010.

  16. Basic quality information

    Some general information on the quality of the Index of Services (IoS) can be found in the “Understanding the Index of Services” section in the main part of this statistical bulletin.

    Additionally, a Quality and Methodology Information (QMI) report for the IoS was published on 11 February 2015. The report pulls together qualitative information on the 5 Eurostat criteria of quality: relevance, accuracy, timeliness and punctuality, accessibility and clarity, and comparability and coherence, and provides a summary of the methods used to compile the IoS output, describing the strengths and limitations of the estimates produced.

    Further quality information, including details of the quality adjustments process for IoS, was published on 31 October 2014 and can be found on the Index of Services methods page on our website.

  17. National accounts revisions policy

    Main documentation explaining the national accounts revisions policy is available.

  18. Revisions triangles

    Standard Industrial Classification 2007 (SIC 2007) revisions triangles are contained in a zip folder. This folder can be found within the data section of this bulletin.

    Revisions to data provide an indication of the reliability of main indicators. A statistical test has been applied to the average revision to find out if it is statistically significantly different from 0. An average revision close to 0 is desirable as it suggests that revisions are not predictable in any 1 direction. The result of the test is that the average revision is not statistically significantly different from 0.

    Table 5 presents a summary of the differences published between May 2010 and April 2015 and the estimates published 12 months later.

  19. Accessing data

    The data presented in the tables of this statistical bulletin are also available to download from the dataset section of this publication. A complete run of data is available as a time series dataset on our website.

  20. Code of Practice for Official Statistics

    National Statistics are produced to high professional standards set out in the Code of Practice for Official Statistics. They undergo regular quality assurance reviews to ensure that they meet your needs. They are produced free from any political interference.

    The UK Statistics Authority has designated these statistics as National Statistics, in accordance with the Statistics and Registration Service Act 2007 and signifying compliance with the Code of Practice for Official Statistics.

    Designation can be broadly interpreted to mean that the statistics:

    • meet identified user needs
    • are well explained and readily accessible
    • are produced according to sound methods
    • are managed impartially and objectively in the public interest

    Once statistics have been designated as National Statistics it is a statutory requirement that the Code of Practice shall continue to be observed.

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Contact details for this Statistical bulletin

Robert Smith
ios.enquiries@ons.gov.uk
Telephone: +44 (0)1633 651618