7. Data sources and quality
The estimates presented in this bulletin contain uncertainty. For more information, see our Uncertainty and how we measure it methodology.
Information on revisions is available in our Labour market statistics revisions policy.
Information on the strengths and limitations of this bulletin is available in Section 13 of our Labour market overview, UK: April 2021 bulletin.
Further information is available in our Guide to labour market statistics methodology.
Revisions
Our Vacancies and jobs in the UK April 2025 bulletin includes revisions of vacancies estimates back to the start of the series in 2001. Revisions to the full-time series from 2001 onwards resulted from a review of the seasonal adjustment parameters. Revisions from November 2021 to January 2022 onwards resulted from taking on additional, updated sources of information. This is a regular annual process, as outlined in our Vacancy Survey quality and methodology information (QMI), which aims to improve the quality of our estimates.
For our Average weekly earnings April 2025 bulletin, we have implemented revisions, on an exceptional basis, back to October 2020 to allow late and updated returns we received from one business to be included and to improve the quality of the estimates. At the whole economy level, the revisions are generally small and within the range we would expect to see during seasonal adjustment reviews. This is because, as the estimates are broken down below the whole economy level, the revisions become larger. The impact of the revisions can be found in our Average weekly earnings supplementary analysis dataset.
Accredited official statistics
On 7 June 2024, the Office for Statistics Regulation (OSR) introduced the new accredited official statistics badge, to denote official statistics that have been independently reviewed by the OSR. Accredited official statistics comply with the standards of trustworthiness, quality and value in the Code of Practice for Statistics.
This UK labour market bulletin includes a combination of accredited official statistics and official statistics in development (until September 2023, these were called “experimental statistics”). Read more about the change in our Guide to official statistics in development.
The following labour market outputs are accredited official statistics:
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Labour disputes (rapid review completed by the OSR in February 2023) Vacancy statistics (reviewed by the OSR in April 2022)
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Workforce jobs (WFJ) (reviewed by the OSR in April 2022)
The following labour market outputs are official statistics in development:
Labour Force Survey
We have been facing the challenge of falling response rates for household surveys, as have other comparable countries. This issue became more acute in the LFS data collected for August 2023. The LFS estimates due to be published in October 2023 were suspended because of quality concerns. We developed a comprehensive plan to address these concerns and reintroduce LFS, as described in our Labour Force Survey: planned improvements and its reintroduction methodology. We reinstated reweighted LFS estimates into our monthly publication from February 2024, as described in our Impact of reweighting on LFS key indicators: 2024 article.
In December 2024, we carried out a further LFS reweighting exercise, based on 2022 mid-year estimates. The population estimates used do not consider the most recent estimates of migration published by the Office for National Statistics (ONS) in November 2024.
It is likely that some of the recent movements in LFS estimates are also being affected by the increased sample size and changes in data collection methods introduced over the last year, in addition to any underlying changes in the labour market.
The wave structure of the LFS means that any changes in sampling can take a substantial amount of time to fully feed through the survey. We interview sampled households at quarterly intervals for five consecutive quarters.
Any given three-month dataset includes respondents completing their first, second, third, fourth, or fifth interview (often called “waves”).
Between July and December 2023, the Wave 1 sample for the LFS was reduced to its pre-coronavirus (COVID- 19) pandemic level, before the boost was reinstated from January 2024. This reduction in the sample stays in our LFS datasets for five quarters, as these smaller cohorts progress through subsequent waves, all the way to Wave 5. From July 2024, the smaller cohorts are steadily being replaced by boosted cohorts. However, it will not be until the January to March 2025 period (published in May 2025) when LFS data only include boosted cohorts.
Reweighting does not address the volatility we have seen in recent periods and which we expect to see to some extent in the future. We would advise caution when interpreting changes in headline rates and recommend using them as part of our suite of labour market indicators, alongside Workforce Jobs, Claimant Count data and Pay as You Earn Real Time Information (PAYE RTI) estimates.
Further information on response rates and other quality-related issues for the LFS can be found in our quarterly Labour Force Survey performance and quality monitoring reports.
Coherence of data sources
Understanding coherence challenges around our employment indicators continues to be a priority.
In April 2025, we published an update on our work on reconciling estimates of employment from the LFS and WFJ. This work makes several adjustments to both LFS and WFJ estimates to try and account for known differences in concepts, coverage, and measurement.
LFS reweighting has improved the coherence picture, as strong population growth in recent years is now incorporated into our estimates of all three labour market statuses.
We are also considering how best to consider coherence between HMRC’s PAYE RTI data and WFJ. As the former is essentially focused on employees, we recommend comparison with the employee jobs component of WFJ to align coverage of populations. One other important difference is that the RTI statistics published each month are a measure of people, rather than jobs, as in WFJ.
Our Comparison of labour market data sources methodology compares data sources and discusses some of the main differences.
Labour market transformation
We have provided an update on the transformation of labour market statistics in our Labour market transformation-update on progress and plans: April 2025 article.
We welcome your feedback on this latest update and our plans. Please email us at [email protected] to tell us what you think.
For more information on how labour market data sources were affected by the coronavirus pandemic, see our Coronavirus and the effects on UK labour market statistics article.
Making our published spreadsheets accessible
Following the Government Statistical Service (GSS) guidance on releasing statistics in spreadsheets, we will be amending our published tables over the coming months to improve the usability, accessibility and machine readability of our published statistics. To help users change to the new formats, we will be publishing sample versions of a selection of our tables and, where practical, initially publish the tables in both the new and current formats. If you have any questions or comments, please email us at [email protected].
Country of birth and nationality labour market outputs
The temporary RTI adjustment applied from January to March 2020 to June to August 2022 was removed from the LFS weighting methodology as part of the reweighting exercise in December 2024, as described in our Impact of reweighting on LFS key indicators: 2024 article.
Because of quality concerns, we have removed the labour market status by country of birth and nationality from our A01: Summary of labour market statistics dataset and from tables accompanying our Labour market overview and Employment in the UK bulletins. Our EMP06: Employment by country of birth and nationality dataset and A12: Employment, unemployment and economic inactivity by nationality and country of birth dataset will continue to be made available on our website. We are continuing to publish these estimates to maintain a complete time series based on a consistent methodology; however, we advise extreme caution when using estimates of labour market status by nationality and country of birth during this period.
From the February 2025 publication, the country of birth and nationality labour market data will be withdrawn from our time series data.
