Estimating the size of the population and how it changes is important. Users of the migration statistics produced at The Office for National Statistics (ONS) have stated that they need more detail about how different groups of the population (in particular international migrants) impact on society and the economy.
ONS is transforming the way they produce population and migration statistics, to better meet the needs of users. Working in partnership across the Government Statistical Service (GSS), it is progressing a programme of work to put administrative data* at the core of evidence on international migration and population (England and Wales) in 2020.
Nicola White, ONS Centre for International Migration opened the session by discussing the ONS and Government Statistical Service (GSS) development plan for international migration statistics, the context for this change and how international migration statistics could look in the future. The main points concerned how it plans to put administrative data at the core of migration and population statistics by 2020 and a timeline of planned progress. Since presenting at the RSS Conference ONS published an update on our population and migration statistics transformation journey on 30 January 2019. This report outlines the progress it is making towards building an administrative-data based system for measuring migration, and asks users of our statistics for feedback.
Hannah McConnell, also from the ONS Centre for International Migration then discussed improvements that have been recently implemented to improve the quality of International migration outputs produced by ONS, specifically the migration statistics quarterly report. The key messages were that other data sources, such as Home Office visa data, are now presented in the quarterly report for comparison with the International Passenger Survey (IPS) data, and that uncertainty around the IPS estimates is now presented visually so that we can reach our best assessment of international migration.
David Matz, Home Office Migration Statistics, Migration and Border Analysis, provided context on the Home Office Exit Checks data, who is covered and what is measured, and the challenges of collecting and these linking data. Despite the caveats of the data source, exit checks data can be used as an indicator of migration alongside other sources.
Nicola Rogers discussed how the Centre for International Migration have used the Exit Checks data provided by the Home Office in the first half of 2018 to understand migration patterns of those on study, work and family visas, and how this work will be taken forward. The publication from this work identified that this data source can contribute to our understanding of international migration, and that people’s movements are complex and do not conform to our traditional statistical definitions of migration.
Alison Reynolds, Centre for International Migration talked about how changes between intended and actual international migration behaviour are captured in the International Passenger Survey, which is the current data source that is used to measure international migration to and from the UK, and whether the current methodology reflects travel patterns seen in administrative data sources. Finally, Jay Lindop, Deputy Director of the ONS Centre for International Migration who chaired the session, provided concluding comments and discussed future meetings and timelines.
Following the presentations, the panel of Jay Lindop, David Matz, Nicola Rogers and Nicola White answered questions and discussed various topics, including the availability and comparability of existing and new data sources that can be used to measure international migration to the UK. Within this session, the challenges of understanding statistical uncertainty in survey and administrative data sources were also discussed.
The session, Official Statistics & Public Policy: Improving & developing international migration statistics, took place on 4 September 2018 at the RSS Conference in Cardiff.
Slides from the session are available to download (PDF)
* Administrative data refers to data collected by other organisations (such as government departments) to support the delivery of services or for other operational purposes.