Population and migration statistics system transformation – recent updates

In response to the impact of the coronavirus (COVID-19) pandemic and the suspension of the International Passenger Survey (IPS), we have reviewed our approach to the transformation of migration statistics.

We have accelerated our transformation plans to use administrative data to deliver new measures of migration and, as previously announced, decided that the August 2020 Migration Statistics Quarterly Report (MSQR) would provide the last set of long-term migration estimates based on IPS data.

In addition, we have looked at a range of other sources of data to provide information on international migration and mobility patterns since the coronavirus pandemic began, and are investigating approaches for estimating international migration for the period April to June 2020. Today (26 November 2020) international migration statistics released include:

• a synthesis report bringing together a range of data sources on international migration and mobility patterns since the coronavirus pandemic

• an update to our Population and migration statistics system transformation – overview article providing information on our latest progress with the development of admin-based migration estimates (ABMEs) and alternative approaches for estimating migration for the period April to June 2020

• Long-term international migration estimates: 2019 – a set of data tables providing final annual data for 2019 based on the IPS

Further planned releases in early 2021 include:

• estimates of population by country of birth and nationality for the period July 2019 to June 2020

These statistics were originally due to be published on 26 November 2020, but have been rescheduled for early 2021 because of delays in the supply of data following work to reweight Labour Force Survey (LFS) data.

• first report on ABMEs

To ensure that we can provide our best possible assessment of how international migration is changing, we now plan to publish our first report on our new ABMEs in early 2021. This revised timetable will enable us to carry out the further analysis required to develop and assure the methods, collaborating with the Government Statistical Service (GSS).

Migration Statistics Quarterly Report (MSQR): August 2020, including long-term international migration estimates for the year ending March 2020

The latest long-term international migration estimates are based on International Passenger Survey (IPS) data for the period up to March 2020. The period in which data were collected from the IPS covers up to 16 March 2020. The IPS was suspended on this date because of the coronavirus (COVID-19). The weighting methodology has been adapted to compensate for these missing data. This compensation means that the reporting period for this release remains unchanged.

As a result of the Migration Statistics Transformation Journey, the IPS being stretched beyond its original purpose, and the impact of the coronavirus pandemic, this will be the last Migration Statistics Quarterly Report (MSQR) based on IPS estimates.

Processing and quality assurance of IPS data for Quarter 1 (Jan to Mar) 2020 identified a possible issue in the data, namely an unexpected large rise in the number of non-EU students interviewed in the IPS.

A detailed review of the data and associated processes suggests this may be because of the IPS being susceptible to sampling variability. This observation aligns with previous analysis, which identified that large numbers of students may travel at the same time because of course start dates, meaning that some IPS shifts may include clusters of student contacts. If this were to occur, the IPS data may overestimate the number of long-term student migrants. This is a limitation of using a sample survey.

Uncertainty of this type in the data is represented by the confidence intervals around the estimates, which can be viewed in the associated datasets. Because of this oversampling, an adjustment, in line with previous adjustments, has been applied to non-EU student immigration for year ending Quarter 1 2020 estimates using Home Office (HO) visa allocations. This ensures we are providing the best possible estimates of migration based on all available sources. See Section 6 of the Migration Statistics Quarterly Report: August 2020 for more detail.

As it is recognised that international travel patterns have changed significantly in 2020 because of the coronavirus pandemic, we have also included in this release additional data and insights on recent travel patterns in the period up to the end of June 2020. See Section 8 of the Migration Statistics Quarterly Report: August 2020 for more detail.

This release presents different migration-related data sources at local authority level including:

• migration flows

• non-UK-born and non-British populations

• National Insurance number registrations

• GP registrations

• births to non-UK-born mothers

We have reduced the content of our Short-Term International Migration (STIM) publication to focus on our migration transformation work and the development of these statistics. Further information can be found in Short-Term International Migration for England and Wales: year ending June 2018.

As a result, the STIM table normally included in local area migration indicators (LAMIS) is not currently being produced. This means that the STIM data included in the LAMIS 2020 release is the mid-2016 to mid-2017 provisional data (previously published in the LAMIS 2019 release).

We welcome any thoughts you have on the development of STIM estimates in the future. If you would like to get in touch, please contact us by email at pop.info@ons.gov.uk.

As part of our transformation journey to make use of all available data sources to provide a richer and deeper understanding of migration, we are moving towards the first publication of an admin-based migration estimates (ABME) report in early 2021. While the ABME report will replace the Migration Statistics Quarterly Report (MSQR) publication, it is important to recognise that the move to ABME reports marks a change in how we will report migration estimates.

As we progress our ambition to maximise the value and benefits of admin data, the initial ABME reports will not report migration data in the same way as the MSQR. The current availability of admin data means that the time periods reported upon in the MSQR, and some of the underlying detail, such as reason for migration, will not be included in our initial ABME reports.

It is important to recognise that this short-term change in content is an important step towards the delivery of a transformed migration system, one that makes best use of all available data sources and underpins a new robust, sustainable and coherent population and migration statistics system.

Our ABME reports will demonstrate iterative progress towards a transformed migration system and will provide users with clear messages on our next steps and challenges. As such, the ABME reports will, like the MSQR, be classified as Experimental Statistics. As our work progresses, we look forward to being able to produce greater insights into migration patterns and statistics at an ever more granular level.

Our transformation mission is to provide the best insights on population and migration using a range of new and existing data sources to meet the needs of our users. This is increasingly important in a rapidly changing policy and societal context, where we know our users need better evidence to support decision-making at both national and local levels.

In addition to the regular outputs described in the earlier sections, we deliver analysis and insights into important migration topics based on user needs. This section summarises the latest analysis and insights from the Centre for International Migration.

Coronavirus and non-UK key workers

On 8 October 2020, we released new insights on non-British nationals and non-UK-born people in the workforce between 2017 and 2019. This includes a focus on those who could be considered as key workers in the response to the coronavirus (COVID-19) pandemic. It also includes interactive maps for users to explore the proportion of non-British national workers and key workers living in local areas.

Previous analysis articles

The following analysis articles include further insights on international migration patterns and sectors:

• What can administrative data sources tell us about the patterns of presence of non-EU students? (February 2020)

• International migration and the healthcare workforce (August 2019)

• International migration and the education sector -- what does the current evidence show? (May 2019)

We welcome your feedback on our latest updates and on our transformation journey. If you would like to get in touch, please contact us by email at pop.info@ons.gov.uk.