ONS Blog: Mary Gregory, Interim Director of Population Statistics, explains what is driving population growth and the progress the ONS is making towards producing new estimates which better meet user needs.

This ONS bulletin includes estimates of:

• rate of population change in regions of England and Wales


• local area population change 


• comparisons with admin-based population estimates (ABPEs)

To support understanding of why ONS are evolving population and migration statistics, they have published a paper explaining the design of the future statistical system for England and Wales.

This includes an overview of the statistical design starting with administrative data, data linkage, coverage adjustment, statistical modelling and a glossary of terms.

This ONS report provides information about the quality strategy underpinning the future population and migration statistics system in England and Wales.

Mid-year population estimates QMI

Quality and methodology information (QMI) for mid-year population estimates in the UK has been updated, detailing the strengths and limitations of the data, methods used, and data uses and users.

Population estimates for England and Wales, mid-2023: methods guide

ONS have also updated the methodology guidance on national and subnational mid-year population estimates for England and Wales.

Population statistics and sources guide

ONS update to their population statistics and sources guide includes comparisons of the different types of population estimates that are published on the ONS website or planned for future publication.

Dynamic population model, improvements to data sources and methodology: local authorities in England and Wales, mid-2011 to mid-2023
Update on the data used by the dynamic population model (DPM) to produce admin-based population estimates (ABPEs).

Understanding mid-year admin-based population estimates for local authorities in England and WalesThis methodology brings together important information about ONS' mid-year admin-based population estimates (ABPEs) for England and Wales.

Mid-year admin-based population estimates for England and Wales QMI
Quality and Methodology Information for mid-year admin-based population estimates (ABPEs) for England and Wales, detailing the strengths and limitations of the data, methods used, and data uses and users.

ONS have published updated data tables following National Records Scotland rebased estimates, drawing on Scotland’s Census 2022.

This dataset covers national and subnational mid-year population estimates for the UK and its constituent countries by administrative area, age and sex (including components of population change, median age and population density).

To inform their judgements around the suitability and quality assurance of the data and methods used in the Dynamic Population Model, OSR commissioned an independent review from Professor Arkadiusz Wisniowski, University of Manchester.

Read the assessment report here.

Comparison of admin-based small area income (official statistics in development) statistics (ABIS) with official accredited modelled estimates and how they meets the Canberra Handbook criteria.

This article provides an update on ONS' research on the development of income statistics for small areas. It forms part of their wider research towards a future population and migration statistics system, detailed in theirdashboard on the topic.

Population projections for the UK are based on assumptions about future births, deaths, and long-term net international migration.This release covers the potential future population size of the UK. These statistics are widely used in planning, for example, fiscal projections, health, education, and pensions.

Read at the article at https://www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationprojections/bulletins/nationalpopulationprojections/2021basedinterim

There are many reasons for wanting to know the size of the future population of the UK. But looking into the future is challenging. James Robards explains how ONS takes into account current and past trends, and as these change, how the assumptions used in projections are adjusted accordingly.

See the Blog at https://blog.ons.gov.uk/2024/01/30/understanding-our-future-population-why-projections-are-not-predictions/

2022-based national population projections, subnational population projections and household projections are due for release at the end of 2024 and in 2025. To help prepare for the new projections, ONS is seeking feedback from users on their output needs from these releases.  

Participate at https://consultations.ons.gov.uk/external-affairs/2022-based-population-projections/

This issue covers:

User needs from Population Projections

2022-based national population projections, subnational population projections and household projections are due for release at the end of 2024 and in 2025.  

To help prepare for the new projections, ONS s seeking feedback from users on their output needs from these releases. Use the feedback survey at https://www.consultations.ons.gov.uk/external-affairs/2022-based-population-projections/

The ONS projections team are also hosting an online event on 20 February, which is an opportunity to discuss the engagement and ask any questions. 

Migration statistics system webinar

ONS is launching its annual Migration statistics system webinar to provide updates and answer questions relating to long-term international migration statistics.

Users are invited to attend the first event on the 20 March for discussion of the methods used to produce provisional and updated net migration estimates, plans for the future and assumption setting process amongst other topics. Register now at https://www.eventbrite.co.uk/e/migration-statistics-system-webinar-tickets-838511960847?aff=oddtdtcreator

Feedback on marital status and living arrangements publications 

As part of its review of publications, ONS is seeking feedback from users on any needs that are not currently being met.

ONS encourages users to provide feedback and responses on the tables that are the most useful. You can do this in two ways, either via the data tables at: https://www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates/datasets/populationestimatesbymaritalstatusandlivingarrangementsengland

or by emailing the Population Statistics team with your comments via the link above.

ONS is currently assessing whether or not its Admin Based Population Estimates (ABPE’s) in England and Wales currently meet the professional standards set out in the statutory Code of Practice for Official Statistics.  The first phase of our assessment will focus on three broad areas: 

1. The suitability and quality assurance of the data and methods used in the Dynamic Population Model to produce population estimates in England and Wales. 

2. The extent to which ONS is benchmarking the state of readiness of population estimates to replace the cohort component method previously used.

3. An initial investigation into user understanding of, and confidence in, the proposed new method, and ONS communications on this. 

More information on the assessment can be found at the website address above. Users’ views with form an important part of ONS’s judgment about the statistics, including how they could be improved. If you are a potential user of these statistics, ONS would be interested in hearing your views on the areas outlined above ideally before 22^nd March 2024.

ONS has published annual population estimates by marital status and living arrangements.  These include the latest data for 2021 and 2022 and revised estimates for 2012 to 2020 to incorporate rebased mid-year population estimates to align with the 2021 Census. The release includes estimates of people who are: 

• married


• civil partnered


• divorced or widowed


• cohabiting (not in a marriage or civil partnership)

ONS has released related data and analyses on life expectancy and estimates of the very old. The releases cover:

National life tables – life expectancy in the UK: 2020 to 2022: This bulletin shows trends in period life expectancy by age and sex for the UK and the constituent countries, reflecting increased mortality in 2020-2022 during the Coronavirus (Covid-19) pandemic. This includes

• estimates of life expectancy at birth in the UK in 2020 to 2022 compared with 2017-2019 and


• life expectancy at age 65 in the UK in 2020 to 2022 compared with 2017-2019.

Estimates of the very old, including centenarians, England and Wales: 2002 to 2022: This bulletin describes changes in the estimated size and age distribution of the 90 years and over population in England and Wales, over time. Comparisons are also made on the numbers and proportions of centenarians over the last two decades, in relation to historic birth patterns one hundred years ago.

ONS has published a suite of population and international migration releases accompanied by a blog by Emma Rourke, Deputy National Statistician. The releases cover:

Behaviour shifts and the implications for migration statistics

Emma discusses the main drivers for migration to the UK, why ONS updates its estimates of international migration and the transformation of the population and migration statistical system. 

Population estimates for England and Wales: mid-2022 including:

• information on population change


• impact of international migration and other factors on population change


• population pyramids and demographics


• comparison with experimental admin-based estimates

Rebasing of mid-year population estimates following the 2021 Census in England and Wales including:

• rebased official population estimates for the period 2012 to 2021


• the impact of improved data


• how the remaining differences have been dealt with

The full detail of the rebased back series, including the revised international migration estimates can be found in the release, alongside summary tables to aid analysis.

ONS has released a similar suite of bulletins and articles on the topics of international migration and population estimates. These releases are accompanied by a blog which provides context on the interdependence of these statistics covering:

Long-term international migration, provisional: year ending June 2023 including estimates of:

• net migration to year-ending June 2023


• migration by reasons for immigration to the UK


• immigration to the UK by non-EU, EU and British nationals

Reason for international migration, international students update: November 2023 providing:

• details on international migration of international students 


• estimates of international students' emigration patterns 


• information on the methods employed for these estimates

International migration, research, progress update provides an update on research to develop admin-based migration estimates (ABMEs), and on ONS’s expansion to the range and granularity of its statistics. It also outlines improvements to methods for measuring uncertainty.

Improving international migration statistics using administrative data:This easily-digestible article explains to users: 

• why ONS has moved from a survey-based methodology to using administrative data


• why this is an improvement


• what the remaining challenges are

Methods to produce provisional long-term international migration estimates summarises and explains the methods utilised to produce the latest provisional statistics on migration flows into and out of the UK.

Understanding international migration statistics brings together important information to inform users and explain any misunderstandings around our migration statistics in one easy-to-read article.

Estimating UK international migration: 2012 to 2021

• explains how we arrived at the revised back series to be used for rebasing of mid-year population estimates


• sets out how migration has changed over the decade


• assures that new methods are robust

Long-term international migration estimates: quality assurance of administrative data provides administrative data sources and quality assurance in the production of admin-based long-term international migration estimates published in bi-annual releases.

ONS has published an overview of upcoming population and migration publications as we make improvements to how we measure population and migration. The article includes information on:

• the ongoing transformation programme of population and migration statistics


• how and why ONS makes revisions to statistics


• next steps in meeting the needs of users 

ONS has published experimental statistics for 2021 and 2022 using data from the Annual Population Survey (APS). The release provides breakdowns by region, sex, age, legal partnership status, ethnic group and socio-economic classification. A bulletin containing discussion of the key findings for 2022 and important differences to consider when considering the 2021 Census results accompanies the dataset.

As the estimates are derived from a survey, measures of uncertainty are provided around the estimates in the tables. The main points of this analysis include:

• the household population of the UK aged 16 and over who identified as heterosexual or straight decreased to 93.4 per cent;


• a continued increase in those who identify as lesbian, gay or bisexual (LGB) to 3.3 per cent;


• men were more likely to identify as gay or lesbian than women, women were more likely to identify as bisexual than men;


• almost 1 in 10 of those aged 16 to 24 years identified as LGB, and how this proportion changes with age; and


• the majority of those identifying as LGB had never entered a marriage or civil partnership.

21 September 2023 issue includes:

Revised release date for population and migration estimates: In order to provide consistent estimates across a number of upcoming publications and ensure these are all based on the most up-to-date information, ONS is changing its publication timetable. As migration statistics feed into mid-year estimates, the mid-year estimates for the year ending June 2022 will be postponed until 23 November.

Dynamic population model: As part of ONS’s work towards transforming population and migration statistics, last year it introduced a dynamic population model (DPM) to estimate the population in a timely way and better respond to user needs. The DPM uses statistical modelling techniques to bring together a flexible range of data sources to produce coherent estimates of the population.

Links to the animated videos in English and Welsh and more information are available on the ONS website.

See https://content.govdelivery.com/accounts/UKONS/bulletins/36fb31f for more information.

18 October 2023 issue included:

Updates on the postponed 2023 population and migration release dates: The provisional dates for the release of the National Population Projections (NPPs) are:

• 2021-based interim NPPs (using Census 2021 and latest international migration estimates and new assumptions) - January 2024


• 2022-based NPPs (using the latest census data (including from Scotland), new assumptions and a range of variants) - October / November 2024


• Subnational population projections (SNPPs) release (England) - Early 2025

ONS is aware of user needs for an updated set of SNPPs and is looking to publish the SNPPs as quickly as practically possible in 2025.

See https://content.govdelivery.com/accounts/UKONS/bulletins/376349f for more details and information on forthcoming releases.

14 December 2023 issues included:

Consultation on the future of population and migration statistics in England and Wales: ONS has published a consultation update which details the number of consultation responses by sector and outlines how it engaged with users of population and migration statistics both before and during the consultation. It also explains how ONS are carrying out its analysis of the responses. 

These responses will inform a recommendation to government from the UK Statistics Authority, on the advice of the National Statistician. This will detail how ONS should produce statistics about population and migration in the future, based on user needs.

Admin Based Population Estimates from the Dynamic Population Model (DPM): ONS has published the latest research update into how it is refining and improving methods to produce Admin-Based Population Estimates (ABPE). The two published articles support the continuous improvement of ONS’s population statistics by demonstrating its ability to produce more timely and inclusive population estimates in a flexible way that makes the best use of all available information. These estimates do not replace or replicate the National Statistics for population estimates.

Listening to its stakeholders: ONS is committed to providing high quality statistics and analysis for the public good.  It has launched its annual ONS Stakeholder Satisfaction Survey and invites users to take part. Their feedback will help ONS improve and ensure that its statistics continue to meet users’ needs.  

The survey can be completed anonymously and remains open until 22 January 2024.

See https://content.govdelivery.com/accounts/UKONS/bulletins/37f5508 for more details and information on forthcoming releases.

18 January 2024 issues included:

National population projections: ONS will be publishing interim 2021-based National Population Projections on 30 January 2024: interim that provide an indication of the potential future population size of the UK and its constituent countries.  

This release will use the latest available population data including 2021 Census data and new international migration assumptions using the latest estimates of international migration.  

It will also use assumptions for cross border migration, fertility and mortality from 2020-based interim NPPs. NPPs are widely used in planning, for example, fiscal projections, health, education, and pensions. 

Update on the consultation on the future of population and migration statistics in England and Wales: On 14 December 2023 ONS published a consultation update that includes the number of responses by sector and outlines how ONS engaged with users of population and migration statistics both before and during the consultation. It also explains how ONS is carrying out its analysis of the responses. Users can read this update on the ONS website. 

Analysis of the consultation responses is ongoing and will be published alongside the publication of the recommendation on the future of population and migration statistics.

See https://content.govdelivery.com/accounts/UKONS/bulletins/3853e42 for more details for other recent and forthcoming releases.

In June, ONS launched a public consultation on its proposals for a new approach to population statistics. User input will be essential evidence in making the National Statistician’s recommendations on the future of population and migration statistics and the census. The consultation is open until 26 October 2023, but ONS has encouraged an early response.

If you have any questions about any aspect of the consultation please contact ONS at outreach.engagement.la@ons.gov.uk

This issue includes:

Consultation on the future of population and migration statistics in England and Wales in which ONS seeks user input as essential evidence for the National Statistician’s recommendations to Government on the future of population and migration statistics in England and Wales.

Invitation to an International migration statistics webinar on 17 August 2023 which sought to determine what international migration statistics users need that are not met by ONS’s official statistics on long-term international migration?

Notification of some of the upcoming releases related to migration and population statistics.?

Social surveys offer immense and uniquely valuable insights into the lives of people up and down the country, and those of ONS are among the very largest conducted regularly in the UK. 

In this episode of Statistically Speaking, podcast host Miles Fletcher chats to members of the ONS Social Survey Collection Division about the importance of these surveys in helping to paint a picture of life across Britain.

This issue includes:

Drivers of international migration which reports that as part of it’s public consultation on the future of population and migration statistics, ONS is seeking views from users about potential alternative definitions and breakdowns of population and migration that it does not currently provide. One of those of which ONS is already aware is the need for more context on the drivers of international migration. The latest National Statistical blog from Jay Lindop, Head of the Centre for International Migration, (see https://blog.ons.gov.uk/2023/07/19/why-people-immigrate-to-the-uk-seizing-the-opportunities-of-administrative-data/) explains how ONS is using administrative data to shed more light on the reasons people migrate to the UK.

A reminder to users to take part in the Consultation on the future of population and migration statistics in England and Wales if they have not already done so.

Travel and tourism update which reports that the travel and tourism reform project exists following a review of travel and tourism statistics that commenced in 2019. In 2022, ONS published a final report which proposed new ways for collecting and presenting these statistics. Following a year of research, ONS has now moved on to the implementation stage of it’s project and have recently released a project update on progress and recent publications.

Developing methods to produce 2021 income data, England and Wales provides an update on ONS’s research to develop census-type income data that can be integrated with the data collected in the 2021 Census.

Feasibility research on producing UK armed forces veteran statistics for England and Wales demonstrates the feasibility of producing statistics on the population who have previously served in the UK armed forces in England and Wales using the Service Leavers Database and the 2021 Census. 

ONS’s public consultation on the future of population and migration statistics includes seeking views from users about potential alternative definitions and breakdowns of population and migration that are not currently provided. One of those ONS is already aware of is the need for more context on the drivers of international migration. In a blog (see https://blog.ons.gov.uk/2023/07/19/why-people-immigrate-to-the-uk-seizing-the-opportunities-of-administrative-data/) Jay Lindop explains how we’re using administrative data to shed more light on the reasons people migrate to the UK.

ONS has been working at pace to produce more timely and reliable population estimates. By using multiple data sources to reduce reliance on a 10-yearly census, it is proposing a new system which would be responsive to change and provide decision makers with the evidence to put the right services in the right places. In this blog (see https://blog.ons.gov.uk/2023/06/27/growing-confidence-in-our-ability-to-move-to-a-new-population-statistics-system/) Jen Woolford updates on progress to date, explains how the new data should be used and looks ahead to this summer’s public consultation.

For the past 200 years the once-a-decade census has been the benchmark for measuring the number of people in the country, but do improvements in technology and greater availability of data now mean that change is on the horizon?  

In this episode of Statistically Speaking (see https://blog.ons.gov.uk/2023/06/21/new-data-transforming-how-we-count-the-population/) ONS discusses how it has been working to transform the way it counts the population, using new datasets to give more accurate, timely, and detailed measurements.

Population and migration statistics underpin decisions and policies right across our society and economy at national and local levels and for different communities. It is therefore vital they keep up with society’s changing needs. On 29 June 2023, ONS launched a public consultation on our proposals for a transformed population and migration statistics system. Understanding user needs will be essential evidence in making recommendations to Government on the future of population statistics. 

This issue includes:

What next for the 2021 Census? in which ONS Director of Population Statistics, Jen Woolford, in her latest blog, sets out the variety of ways in which people?will be?able?to?access?the census statistics they need?in coming months.?ONS is making the latest census information as easy as possible to?use online?so everyone can navigate the?breadth and?depth of census information and find reliable answers to their?questions.  

Create a custom data set combining multiple variables using the 2021 Census in which ONS announces that it is releasing multivariate data from the Census based on the usual resident population of England and Wales. These data will allow users to combine different variables and look at the relationships between the data, providing them with rich insights into the characteristics of the population of England and Wales.  

Why not explore ONS’s exciting ‘Create a custom dataset' tool.  This enables users to build their own datasets using millions of possible combinations of variables and classifications.  

Further pre-built multivariate datasets will be published in accordance with the ONS release schedule, giving users the ability to select geographies. See more details at https://www.ons.gov.uk/datasets/create

The changing picture of short-term international migration in England and Wales in which ONS published the second in its series of detailed articles using 2021 Census data to provide insight on the topic of international migration. This article focuses on non-UK-born short-term residents - those planning to stay for less than 12 months - who were living in England and Wales on Census Day.  The report includes information on their country of birth, economic activity and industry, as well as other characteristics.

Profile of the older population living in England and Wales which provides an overview of the characteristics of people aged 65 years and over living in England and Wales in 2021, including legal partnership status, living arrangements, ethnicity, religion, health, disability, caring status and changes since 2011.

The international student population in England and Wales which reports on an analysis data from the 2021 Census of the characteristics of the international student population of England and Wales, including country of birth, age, sex, employment status, industry, housing type and language spoken

ONS has published a package of population and international migration releases; accompanied by a blog that provides context on progress to date and plans for the future (see following item).

International immigration to the UK hit record levels in 2022, driven by unprecedented world events and the rise in international students following the lifting of pandemic restrictions. Aligned to a period where a new immigration system had recently been introduced, Jay Lindop explains what ONS has been doing to provide users with the best possible migration figures and how these feed into its future model for population statistics (see https://blog.ons.gov.uk/2023/05/25/international-migration-hits-new-high-in-2022-but-there-are-signs-of-change/)

This issue includes:

Latest migration estimates up to year ending December 2022. This includes revisions to some of ONS’s previous estimates from 2018 onwards based on improvements to its methods. Jay Lindop gives a detailed summary of recent ONS releases, and what to expect in the future in her blog (at https://blog.ons.gov.uk/2023/05/25/international-migration-hits-new-high-in-2022-but-there-are-signs-of-change/)

Plans for population and migration estimates and updated timings for publishing the latest population and migration estimates. Further details can be found in the statement on the ONS website (see https://www.ons.gov.uk/news/statementsandletters/provisionalplansforpublishingthelatestpopulationandmigrationestimates)

Custom dataset tool is a component of ONS’s 2021 Census multivariate data release which will provide data on alternative and small populations, origin destination, microdata, detailed migration and others.  

Assessing the benefits of the 2021 Census which reports that over the coming months ONS will engage with many users to understand the realised economic benefits of 2021 Census data. Initially, ONS will be speaking to organisations who contributed evidence to the forecast exercise, so that it can understand whether the data is being used as envisaged and whether the benefits are being realised as expected. This is a separate exercise to the upcoming consultation on the future of population and migration statistics, and focuses on understanding, evaluating and quantifying the economic benefits of the 2021 Census.

ONS published data from the Labour Force Survey detailing trends in living arrangements in 2022 including families (with or without dependent children), people living alone and people in shared accommodation broken down by size and type of household.

This release provides the number of electoral registrations for Parliamentary and local government elections as recorded in the electoral registers for England, Wales, Scotland and Northern Ireland for 1 December 2022.

This issue includes:

Reconciling the census based and rolled forward mid-year estimates for 2021 in which recently published estimates of the mid-2021 population constructed without using 2021 Census data have been created by rolling forward from the mid-2020 estimates, which were rolled forward from 2019 and so on back to the 2011 Census. This article contains comparisons between those two estimates and explores what might have caused the difference between them.

Transforming population statistics, comparing 2021 population estimates in England and Wales:  An overview of the recent population statistics that have been published, and progress update towards a transformed population statistics system. This includes comparisons between census-based and admin-based population estimates and the 2021 Census. 

Admin-based population estimates for local authorities England and Wales: 2011 to 2022  describing ONS’s latest admin-based population estimates (ABPEs) and an update to its research into the dynamic population model (DPM). The DPM seeks to produce coherent and timely estimates of the population and how it changes. ONS has produced ABPEs for mid-year 2011 to 2022 for all 331 local authorities in England and Wales. ABPEs for June 2022 showed a 0.8% increase on the June 2021 estimates.

Delay to publication of outputs awaiting the rebasing of population estimates: Mid-year population estimates are a key input to a number of ONS’s demographic releases. ONS has decided to delay the release of these outputs from their usual schedules so that they can incorporate the latest available population estimates and the rebased back series of population estimates from mid-2012 following the 2021 Census.  This affects: National Life Tables 2019-2021; Estimates of the very old, including centenarians, 2002 to 2021; Childbearing for women born in different years, 2021; and Population estimates by legal partnership status and living arrangements, 2021 and 2022.

Developing subnational multivariate housing by ethnicity statistics from administrative data, England and Wales, 2020, describing ONS’s feasibility research on producing multivariate housing by ethnicity statistics for England and Wales using administrative data. By combining admin-based housing and admin-based ethnicity datasets ONS has been able to determine that the proportion of addresses which had at least one property characteristic, at least one person resident and at least one person with a stated ethnicity was 79.0% for England and 78.1% for Wales. This work forms part of progress towards producing more frequent subnational multivariate statistics on population characteristics.

Developing subnational multivariate income by ethnicity statistics from administrative data, England and Wales: tax year ending 2018, providing an update to ONS’s feasibility research on producing multivariate income by ethnicity statistics on the population from administrative data. By linking together admin-based income and admin-based ethnicity datasets, ONS has produced an income and a stated ethnicity for 77.1% of people in England, and 82.1% of people in Wales, aged 16 years and over in the Statistical Population Dataset (SPD) v3.0, tax year ending 2018. This research is the first time we are presenting this data for both England and Wales.

ONS has published its reconciliation of mid-year population estimates with the 2021 Census at local authority (LA) level.

Reconciliation is the process of comparing the new official mid-year population estimates for mid-2021 (derived from using 2021 Census data), with the mid-year population estimates for mid-2021 rolled forward from 2020. The rolled forward estimates indicate what we would have estimated the population to be in the absence of the 2021 Census.

The comparison of the two different types of population estimates shows how much inter-censual drift there has been. For example, how much potential error has affected the population statistics system over the years between 2011 and 2021.

This issue includes:

Mid-2021 Population estimates for the UK, England and Wales, Scotland and Northern Ireland, providing official estimates of the population at the UK, country, regional and local authority level. They show the population of the UK at mid-2021 was estimated to be 67 million, an increase of about 3.7 million (5.9%) since mid-2011. The release includes information about the components of population change – births, deaths and migration, both international and internal – in the year to mid-2021.

New 2021 Census topic summaries, including most recently, housing, sexual orientation and gender identity, and education. The final bulletin on health, disability and unpaid care was also released on the 19 January 2023. Alongside the topics, the following interactive products have also been published and are receiving positive reviews.

• Census maps


• Voices of our ageing population: living longer lives


• 2021 Census dictionary

Developing the admin-based housing stock profile for England and Wales: ONS has published new feasibility research on developing admin-based housing stock statistics for England and Wales for 2020 as well as summary statistics to create an admin-based housing stock profile. This research explores the feasibility of using Valuation Office Agency (VOA) data and the ONS’s residential address frame to produce census-like housing stock statistics.

Developing admin-based income statistics, England and Wales for the tax year ending 2018 including the first release of an accompanying quality and methodology information report. This continues ONS’s investigation into the feasibility of using administrative data to measure income for small areas.

Unique beta testing opportunity for researchers: linkage of the 2021 Census 2021 to the Longitudinal Study: This is the 6th set of census data to be linked and the LS will then hold data spanning 50 years. ONS is offering a unique opportunity for a select group of researchers to help with its beta testing stage. These researchers will have early access to run approved projects using the new data to help assess whether or not the new dataset is fit for purpose.

Prospective new method for setting mortality assumptions for national population projections: ONS is seeking feedback from its users on the impacts and implications from a prospective change to the method for producing mortality projections.

This data-only release provides new international migration assumptions that have been developed following the latest expert advice and latest provisional estimates of international migration. These projections are a variant of the previously published 2020-based interim projections and are available for: United Kingdom, Great Britain, England and Wales, England, Scotland and Wales.

This issue includes news about:

•  Completion of phase 1 of the 2021 Census results;


• Changing picture of long-term international migration, England and Wales (2021 Census);


• Characteristics of UK Armed Forces Veterans, England and Wales (2021 Census);


• Prospective new method for setting mortality assumptions for national population projections;


• Local authority district case studies of student populations in dynamic population model pilot areas;


• 2020-based interim national population projections


• Design and plans for the 2021 Census Data Asset longitudinal data source for population in England and Wales;


• Developing admin-based ethnicity estimates for England and Wales; and


• People's living arrangements in England and Wales

Advance notice of some of the ONS releases that are scheduled for February and March is also given.

Reconciliation is the process of comparing the new official mid-year population estimates for 2021 (derived from using 2021 Census data), with the mid-year population estimates for mid-2021 rolled forward from 2020. The rolled forward estimates indicate what we would have estimated the population to be in the absence of the 2021 Census .

The comparison of the two different types of population estimates shows how much inter-censual drift there has been. For example, how much potential error has affected the population statistics system over the years between 2011 and 2021, as we add in vital events (births and deaths) and migration.

This article includes information on the possible causes of the differences and examines the impacts of the differences on the age and sex make-up of the population, and at the country and regional levels.

This article explains the prospective mortality projections methodology and highlights findings from comparing this methodology with 2018-based and 2020-based interim national population projections produced using current ONS methodology.

The UK population estimates for mid-2021 provide official estimates of the population at the UK, country, regional and local authority level. They show the population of the UK at mid-year 2021 was estimated to be 67 million, an increase of about 3.7 million (5.9%) since mid-year 2011, 10 years earlier.

The release includes information about the components of population change in the year to mid-2021 – births, deaths and migration, both international and internal.

The latest news and updates about ONS’s transformation to admin data-based statistics on population, migration and census.

Census results are coming in thick and fast, but in parallel the ONS is full steam ahead with new and established methods to shed light on population change since Census Day. With the census having taken place in unprecedented times of a pandemic, Jen Woolford explains how research to transform the whole population statistics system is reaching new milestones while official statistics shed light on times of domestic and global upheaval. 

The ONS has published articles relating to population estimates, the methods behind them, how they will be informed by the 2021 Census results, and a framework to provide feedback on its population estimates.

Accurate and truly representative population statistics are central to the ONS mission of data for the public good. Following the successful enumeration phase in March 2021, ONS is pulling out all the stops to make sure its numbers reflect recent and ongoing population changes. Jen Woolford explains how ONS is prioritising this important work and collaborating in new ways to deliver it. (See also https://content.govdelivery.com/accounts/UKONS/bulletins/32b4b19).

ONS has released an article looking at three measures of average lifespan: life expectancy at birth, median age at death, and modal age at death to understand patterns of mortality from 1841 to 2020 in England and Wales. It also considers future prospects for mortality using projections of life expectancy for 2021 to 2070.

It’s bad news for the Nigels, Carols, Gordons and Cheryls of the world as shifting fashions consign their names to near extinction. Speaking on the latest episode of the Office for National Statistics’ podcast series “Statistically Speaking”, Dr James Tucker of the ONS explains how the annual list of the top baby names in England and Wales unfailingly reflects changing times.

The coronavirus pandemic has led to huge changes in all our lives. Understanding international migration when people’s movement was restricted to manage COVID-19 as well as at a time of change following Brexit has been challenging. In this blog, Jay Lindop provides insights into the work of ONS to estimate migration flows during this period as well as its wider population plans for the coming months.

On 14 April ONS published a new article on subnational population projections for England that aims to help users of subnational population projections to understand the fit of the 2018-based subnational population projections principal and variant projections when compared with the mid-2019 and mid-2020 population estimates. It also provides updates on plans for 2021-based national population projections, subnational population projections and household projections.

Winter 2021 edition, 17 December 2021https://content.govdelivery.com/accounts/UKONS/bulletins/3016238

Spring 2022 edition, 14 April 2022https://content.govdelivery.com/accounts/UKONS/bulletins/31

In these editions you will find news on recent and upcoming releases and events, together with updates on the work that ONS has been doing in the last two quarters.

Trends in living arrangements including families (with and without dependent children), people living alone, and people in shared accommodation, analysed by size and type of household. This release is based on the Labour Force Survey data

On 25 February 2022, ONS published its annual Overview of the UK population. The overview provides a summary of the UK population in 2020, highlighting the changes and the factors which contribute to this. It focuses on the components of population change over time, including fertility, migration and mortality.

On 28 January 2022 ONS published an update on its work to address the recommendations in the Office for Statistics Regulation (OSR) review of ONS population estimates and projections. It also published uncertainty measures for the latest (mid-2021) official population estimates.

Alongside this ONS also shared an update on population estimates for the year ahead, together with a blog which explains what users can expect, how our future research fits in and our current view on what the future of transformed population and migration statistics might look like for our users.

On 12 January 2022, the Centre for Ageing and Demography at the ONS has released 2020-based interim national population projections, Past and projected period and cohort life tables and a blog to accompany the projections release.

Our population is ever-changing and having an up-to-date picture of the ethnic and religious diversity of England and Wales is crucial for policy makers and providers of public services. Previously, the official estimates of the population by ethnic group and religion were from the 2011 Census. Ahead of Census 2021 results, Sarah Coates explains how ONS has responded to the on-going need for data on these areas by producing new, experimental statistics.

On 16 December 2021, the Centre for Ageing and Demography at the Office for National Statistics have released population estimates by marital status and living arrangements, England and Wales for 2020.  Data on marital status and living arrangements in England and Wales are now available to download, including estimates for England and separately for Wales, by age, sex, legal partnership status and cohabitation status.

New analysis on people coming to the UK and holding multiple visas over time. Focus on students coming to the UK and what they do next, alongside workers, and the route to UK citizenship.

On 26th November ONS published research on transforming  population and migration statistics, based on  their approach to make best use of all available data to produce the best possible statistics at a point in time.  This includes an update on their recent progress in this transformation journey, summarising and signposting the detailed research. The Centre for International Migration is publishing an overview of how ONS intends to integrate admin data with statistical modelling to produce coherent international migration estimates. They are also sharing further research which develops our understanding of  admin-based population estimates (ABPEs) for England and Wales in more depth, including their first time series, as well as research into how the student population appears in administrative data.

New figures suggest that although net international migration to the UK fell in 2020, there is no evidence of an exodus. Jay Lindop explains what can be interpreted from today’s experimental statistics, why they shouldn’t be compared to population figures and ongoing improvements to build and refine them.

Today the Centre for International Migration has published our best estimates of long-term international migration in 2020, as well as the population of the UK by country of birth and nationality for the year to June 2021. Alongside these releases, we have published a blog explaining the differences between these two sets of statistics, and when you should and shouldn’t compare them.

The pandemic has highlighted the need for more frequent data about our population to understand the biggest challenges facing society. The ONS has been making great strides bringing together new sources of information to build the richest picture possible. As Pete Benton explains, this week we are publishing the improvements we have made, the limitations in the estimates, and our ambitions to refine the work in 2022.

The aims of this user guide are to provide guidance and examples for those wishing to understand and use variant projections in policy and planning. It covers the national population projections, subnational population projections and household projections.

Welcome to the autumn 2021 edition of the migration and population statistics newsletter.  In this edition news on recent and upcoming releases and events, together with updates on the work we have been doing in the last quarter.

Today ONS has published  National life tables - life expectancy in the UK: 2018 to 2020. The headline from the release is that life expectancy at birth in the UK in 2018 to 2020 was 79.0 years for males and 82.9 years for females; this represents a fall of 7 weeks for males and almost no change for females (a slight increase of 0.5 weeks) from the latest non-overlapping period 2015 to 2017. 

For the first time in four decades life expectancy for men in the UK has fallen. But what does that actually mean, what are the latest trends for women and is this just a blip caused by the pandemic? Pamela Cobb investigates.

Today the Ageing team in the Centre for Ageing and Demography published the latest Estimates of the very old, including centenarians, UK: 2002 to 2020. These provide official estimates of the age 90 and over population for the UK, England and for Wales at single year of age up to age 105 and over and by sex. They show the number of centenarians in the UK at mid-year 2020 rose to their highest ever level in 2020 reaching 15,120, an increase of almost a fifth from last year. This was driven by people turning 100 years old, born in the post-World War One birth spike. The release includes information about how historic birth patterns influence the age 90 and over population, age group comparisons for this population, and UK constituent country comparisons for centenarians.

Today we’ve published mid-2020 Population estimates for Super Output Areas, electoral wards, Parliamentary constituencies, Clinical Commissioning Groups and National Parks. The headline point is that in the year to mid-2020 the population of England and Wales continued to grow with the population in areas described as Cosmopolitan student neighbourhoods experiencing the highest increase at 1.8%.

Today the Ageing Analysis team in the ONS Centre for Ageing and Demography have released Living longer: impact of working from home on older workers . The headline point is that the early exit of older workers from the UK labour market, between the age of 50 years and prior to State Pension age (SPA), can negatively impact an individual's future financial security and is also detrimental to the wider economy

Using new methods, the Office for National Statistics has, for the first time, been able to provide insights into the health outcomes of different ethnic groups. In this blog, Julie Stanborough explains why this experimental data is so important and outlines some of the complexities behind the statistics used.

ONS does not currently produce annual statistics by local authority on the population by ethnic group and the last official statistics were from the 2011 Census. Today, as part of our population and social statistics transformation programme, we have published two articles on our research into the feasibility of producing statistics on the population by ethnic group from administrative data. 

On Thursday 29 July we will be publishing our future plans for population estimates and projections and responding to the OSR review of population estimates and projections. In our publication, letter and accompanying blog we will explain our future plans and invite feedback on our plans. We will subsequently provide updates on our progress to meet OSR’s recommendations between now and May 2022 and we will publish a timeline of planned work with our next update. Our transformation work continues to evolve and there will be further updates in the future.

The recent census in the UK, taken in March 2011, may also have been our last – since the Office for National Statistics has announced that it intends to explore alternative more cost-effective options for ‘census taking’ in the future. In this paper, we consider what the options may be, based on approaches and experiences from other countries, and assess their implications for users. We start by reminding ourselves about the value of the census and the strengths and weaknesses of the current approach. We then identify the principal methods being followed in other countries, together with their advantages and disadvantages. This leads us to review methodological work in the UK, building up to the current ‘Beyond 2011’ ONS project. We focus on administrative records as a possible way of removing the need for a full population survey. Finally, we assess the options and discuss the implications for users in market research.

At the end of 2016 ONS published their first Administrative Data Census research outputs on income. These outputs are the start of ONS research to assess whether it’s feasible to produce income outputs from administrative data. This release produces local authority level individual gross annual income distributions.

A blog by ONS discussing how ONS is refining its approach to gathering and using administrative data – information people have already supplied to other government bodies – to produce census-type outputs.

This research project, being conducted at Southampton University, is looking to discover indicators that could help to estimate census variables, existing large-scale geo-coded transactional datasets such as telephone calls and smart meter usage. The project has tested the utility of a range of analytic techniques for deriving traditional and novel small area socio-economic indicators including relatively simple ratios and distribution measures as well as more experimental temporal sequence and profile analysis.

This ONS work presents results from continued research into a different methodology of estimating the household population using administrative data. This is part of a series of Administrative Data Census Research Outputs the first which was published in October 2015.

The aim of the conference was to inform stakeholders about the latest research, get feedback on the statistical design of the 2021 Census and Admin Data Census and reinforce confidence in the Census Transformation Programme’s delivery of a successful programme.
ONS presented research and plans around the move to a predominantly online census in 2021 and the potential move to an administrative data-based census after 2021. This included making the best use of all available data sources that are needed to produce better statistics for making better decisions.

This presents ONS research and population statistics based on a different methodology to that currently followed in the production of official population statistics. A Statistical Population Dataset (SPD) makes use of linked administrative data to estimate population. These research outputs are NOT official statistics on the population.

In these statistics, ONS brings together data from the Pay As You Earn and benefits systems to derive experimental estimates of gross and net income.

The web page for ONS annual assessments on progress made towards development of an Administrative Data Census.

This ONS page summarises the data sources being used for the experimental Administrative Data Census research outputs, as well as those sources being evaluated for use in the 2021 Census.

The ONS page summarising experimental outputs produced as part of the research into using administrative data to produce population and census statistics in the future.

As part of the ONS’s drive to ensure that its statistics reflect the experiences of everyone in society it has established a new Inclusive Data Taskforce. In this blog (11 January 2021) Chair of the Taskforce Dame Moira Gibb explains the importance of this work and how users can offer their views.

The number of parliamentary electoral registrations at 2 March 2020 was at the highest level ever recorded. This increase, compared to December 2019, reflects the full uplift due to the most recent General Election.

ONS has published (18 January 2021) two reports showing research into the use of Valuation Office Agency (VOA) data to produce overcrowding statistics:

Estimating the number of rooms in Census 2021: an update on deriving an occupancy rating from Valuation Office Agency number of rooms

ONS plans to use administrative data from the Valuation Office Agency (VOA) to replace the number of rooms question in the 2021 Census. This report looks at the impact the use of VOA data on number of rooms has on room occupancy ratings, outlining the method we plan to use to account for definitional differences and asking users for feedback on the method.

This report considers the potential for using VOA data on number of bedrooms to support the production of sub-regional estimates of overcrowding in intercensal years (which the current surveys are unable to do due to sample size).

ONS has released (14 January 2021) an overview of the UK population. This includes information on how the population has changed, why it has changed and how it is projected to change into the future.

ONS has released (14 January 2021) mid-2020 estimates of the population of the UK by country of birth and nationality.

The December 2020 edition of the migration and population statistics newsletter, published on 14 December 2020, includes news on recent and upcoming releases and events, and updates on the work that ONS has been doing in the last quarter.