The tables published today provide estimates of internal migration moves broken down by age and sex at country, region and local (and unitary) authority level for England and Wales. Estimates have also been published which show moves between the constituent countries of the UK.
The estimates published are produced using a combination of administrative data and currently represent the best available source of information on movements within England and Wales. Internal migration estimates by local authority are published on an annual basis, usually around 12 months after the end of the migration period and are timed to coincide with the publication of the mid year population estimates.
As well as being of interest to the media and the general public, internal migration estimates are used by Government and local government.
Academia and special interest groups use the estimates as inputs to their own population models. Internal migration is a key component of population change and is used in the production of mid year population estimates and sub-national population projections.
This bulletin presents statistics on levels of internal migration within England and Wales and between its regions and local authorities, and also looks at international comparisons.
For the year ending June 2011, there were an estimated 2.59 million moves within England and Wales. This represents a decrease of 1 per cent compared with the year ending June 2010.
Figure 1 shows overall numbers of internal migration moves have remained at similar levels over the past 10 years, peaking at 2.77 million moves in the year ending mid-2007. An estimated 5 per cent of the mid-2010 England and Wales population moved to a different local authority in the year to mid-2011.
The aim of this bulletin is to focus on moves within England and Wales; however the mid-2011 estimates also show there were an estimated 38,700 moves from Scotland to England and Wales and 8,700 moves from Northern Ireland to England and Wales. An estimated 41,300 people left England and Wales to live in Scotland and 8,100 people left England and Wales to live in Northern Ireland.
Figure 2 shows the age distribution of moves for the year ending June 2011 as a proportion of mid-2011 population estimates. It can be seen that, consistent with previous years, young adults were the most likely to migrate. Around 1 in 5 of those living in England in mid-2011 aged 19 had moved to a different local authority during the previous year; this constitutes around 6 per cent of all migration moves in mid-2011.
Another peak can be seen in those aged 22; with 16 per cent of all 22 year olds in mid-2011 having moved to a different local authority. The general pattern of peaks is also seen when the data is split by the sex of movers. The commonest age for moving to a different local authority was 19 for both males and females.
There was a small difference in the second peak when incorporating sex, as more males moved aged 23, whereas for females it was more common to move at age 22. These peaks can largely be explained by moves to and from university or other higher education institutions.
Figure 3 shows net regional flows for the year ending June 2011. The figures showed the London region had the largest net difference with an estimated 40,000 more migrants leaving than arriving. The London region had the largest turnover of internal migrants in England and Wales with 201,600 estimated moves into the region and 242,000 estimated moves out of the region, and this represents around 5.5 per cent of its mid-2011 population estimate.
The North East region had the smallest net difference with an estimated 2,700 more migrants leaving the region rather than arriving. The North East also had the smallest turnover of migrants and this is perhaps unsurprising as it does have the smallest population of all the regions in England and Wales.
In terms of regional population gains due to internal migration, the South East region had the largest positive net difference with an estimated 20,700 more migrants arriving then leaving and this net difference represented around 0.2 per cent of its mid-2011 population estimate.
London is an interesting region within England and Wales; whilst its population continues to rise, it remains the region with the largest net outflow of internal migrants. In the year ending June 2011, an estimated 40,400 more people left the region than arrived, this represented a reduction of approximately 2,500 in net outflow for the London region when compared to the previous year. This change in the net level of internal migration was consistent with a general trend of a reduction in the net outflow of migrants for the London region over the last ten years.
In total, Wales had an estimated net gain of 2,500 internal migrants for the year ending June 2011. As a proportion of the regional population, it represents an overall increase of 0.08 per cent and this was the smallest net change for any of the regions in England and Wales. An estimated total of 990 net moves from the North West represented the highest number of people moving to Wales from another region in England and Wales.
The width of each arrow is proportional to the number of people migrating out of London to the regions in England and Wales.
As Figure 4 shows, for the year ending June 2011, 59 percent of all London internal migrant moves were within the London region, whilst the other 41 per cent of internal migrants moved to other regions in England and Wales. Moves out of London in mid-2011 were most likely to the neighbouring regions of the South East and the East of England.
The South East region was the destination for around 40 per cent of the moves out of London with approximately 6 out of 10 of these movers being aged between 16 and 44. It was different for people aged 45 and over moving out of the London region, as the highest proportion (19 per cent) moved to the East region.
Figure 5 illustrates the net migration effect on population at local authority level and highlights areas that either have a net gain or a net loss of internal migrants. As seen in previous years, the net internal migration effect on total population was small for most areas. An estimated 61 per cent of local and unitary authorities recorded a net flow of fewer than 500 migrants.
Around 95 per cent of local and unitary authorities recorded net flows of less than 1 per cent of their mid year population estimates. Around 70 per cent of local authorities in London had a net loss of internal migrants and this is reflected in the inset map included in Figure 5. In the North West region, 25 out of a total of 39 local authorities recorded a net loss in movers.
However in general in the North West region, the majority of the net flows were small with only three local authorities having an estimated net flow of greater than 1000 migrants.
As indicated in Tables 3 and 5, the three local authorities with the biggest inflows and outflows in mid-2011 were Birmingham, Manchester and Leeds. All of these local authorities have universities with large student populations and around 46 per cent of in-migrants and 37 per cent of out-migrants were aged 16-24.
|Area Name||Absolute Net||Net as a % of MYE population|
|Kingston upon Hull, City of UA||2,589||-1.0|
|Area Name||Absolute Net||Net as a % of MYE population|
|Kensington and Chelsea||2,039||-1.3|
|Area Name||Inflow||Net as a % of MYE population|
|Bristol, City of UA||25,195||5.9|
|Area Name||Inflow||Inflow as a % of MYE population|
|City of London||886||12.0|
|Hammersmith and Fulham||17,135||9.4|
|Area Name||Outflow||Outflow as a % of MYE population|
|Bristol, City of UA||24,928||5.8|
|Area Name||Outflow||Outflow as a % of MYE population|
|City of London||854||11.5|
|Hammersmith and Fulham||18,217||10.0|
Newham for the third successive year had the largest net outflow of all local authorities in England and Wales. In total, 7,424 more people left than arrived and this represents around 2.4 per cent of its mid-2011 population estimate. Cornwall UA was the only local authority in the top ten absolute net flows with more migrants arriving than leaving and had a net total of 4,227 in-migrants.
Expressing internal migration flows as a percentage of individual local authority population estimates helps to clarify the impact of internal migration for the overall population in each local authority area. When using this measure, Table 1 shows that the mid-2011 populations of Cambridge and Oxford had the biggest impact from internal migration outflows and inflows.
Around 11 per cent of the mid year populations left the two local authorities and an estimated 10 per cent of their mid year populations arrived. The large student populations in the two areas are likely to have had a major impact on the levels of internal migration as an estimated 35 per cent of those arriving and leaving were aged 20-24.
In Wales, the largest inflows, outflows and net flows were all found in Cardiff UA. This is unsurprising as it has the largest mid-2011 population out of the 22 unitary authorities in Wales, and with an estimated 38,600 internal migration moves, was more than twice as many inflows and outflows as Swansea (area with the next largest flows).
The largest estimated net outflow in Wales was for Rhondda Cynon Taff UA with around 570 more internal migrants leaving then arriving. This unitary authority has consistently recorded a net outflow since mid-2008. The overall impact of net migration on Welsh area populations was small with Conwy being the only unitary authority having a net flow of more than 0.5 per cent of its mid-2011 population estimate.
The 2001 data covering internal migration previously published by Eurostat, suggest the UK has had relatively high rates of internal migration compared to other EU countries, with about 3.5 per cent of the UK population moving between NUTS3 areas in that year.
Caution should be taken when making international comparisons due to differences in geographies and definitions. The magnitude and patterns of internal migration remain poorly documented in many countries, particularly in the developing world, due to the lack of sufficiently detailed source datasets being collected on a consistent basis.
As there is no single system to record population movements within England and Wales, internal migration estimates must be derived from proxy sources. Three administrative data sources are used, namely the National Health Service Central Register (NHSCR), the Patient Register Data System (PRDS) and the Higher Education Statistics Agency (HESA) data.
Overall, the accuracy of NHS based data depends on patients re-registering with a new doctor when they change residence or informing their current GP of any change of residential address. It is known that re-registration rates vary by sex and age group.
Despite some limitation, research has shown that there is no one other available source that has as good coverage and quality as the combinations of these data sources. Detailed information on the methodology and limitations are available on the ONS website in a Quality Methodology Information Document (144.5 Kb Pdf) .
The combination of data sources ensures that the majority of moves are covered for England and Wales. However, given that not all moves are covered there will be some error around these estimates to the level of detail supplied in the tables. It would be appropriate to treat the estimates as reliable when calculating population estimates for a local authority or when assessing whether internal migration for a particular local authority has risen or fallen over time.
To improve estimation of student migration within England and Wales and following a period of user consultation, an additional adjustment for students based on HESA data was introduced by ONS in 2010. Tables from mid-2002 onwards were revised to include the new adjustment. When looking at time series data it is important to remember that estimates for years prior to mid-2002 have not been adjusted for students. Detailed information on the student adjustment has been published on the ONS website in a Methodology Paper (494 Kb Pdf) .
To accompany this release, ONS are presenting a new interactive map of internal migration flows for England and Wales. Figure 6 includes an example output from the interactive map showing the pattern and level of internal migration flows from a local authority. The map is based on the internal migration by local authorities in England and Wales, mid-2011 data release and uses over 60,000 internal migration flows within the visualisation.
The map can be used to visualise the flows between selected local authorities and also displays levels of inflows and outflow of migrants to a particular area. The significant flows between local authority areas are highlighted in orange. The interactive output of internal migration flows for England and Wales using the mid-2011 data release is available on the Neighbourhood Statistics website as an Interactive Map.
This is an example for visualisation purposes only of the internal migration interactive map displaying flows to and from a local authority.
A link to the interactive map is available in the Statistical Bulletin.
Internal migration moves are defined here as moves between local authorities.
Net internal migration is defined as the difference between the number of people moving in and the number of people moving out of a specific area.
Local and Unitary authorities are administrative authorities. For more information on these and other geographical areas see the ONS website.
The structure of single-tier unitary authorities was established in Wales in 1996, more details available on the Welsh Government website.
The full mid-2011 population estimates are available on the ONS website.
European data was obtained from the European Office for Statistics (Eurostat) website.
Nomenclature of Units for Territorial Statistics (NUTS) was created by Eurostat as a single hierarchical classification of spatial units used for statistical production across the European Union. At the top of the hierarchy are the individual member states of the EU: below that are levels 1 to 3. In England and Wales, NUTS3 areas are the equivalents of counties or groups of unitary authorities. For more information, please see the ONS website.
Status of the estimates: Internal migration estimates by local authority are National Statistics. The estimates were re-assessed by the United Kingdom Statistics Authority in summer 2009. The full report can be viewed on the United Kingdom Statistics Authority website.
Methodology: The estimates are produced using a combination of NHSCR, PRDS and HESA data. A detailed description of the methodology used to create internal migration estimates is available on the ONS website.
The internal migration estimates within England and Wales outputs are typically published in June each year. To fit in with the publication plans for the 2011 Census of England and Wales, the release of the internal migration estimates within England and Wales, year ending June 2011 was rescheduled to September 2012.
The estimates used in the bulletin are based on moves within England and Wales. The tables also show moves around the UK. Included for the first time in this release are ‘Table 2b’ outputs and these include moves broken down by broad ages into and out of each local authority within each of the regions in England and Wales. The full set of tabulations published today can be accessed from the ONS website.
Further improvements to methods used to estimate the internal migration of students are being investigated. Details of proposed improvements will be published on the ONS website.
Estimates of internal migration moves within Scotland are produced by the National Records for Scotland (NRS) formerly the General Register Office for Scotland (GROS). For more information please see their website.
Estimates of internal migration moves within Northern Ireland are produced by the Department of Finance and Personnel (DFP) Northern Ireland. For more information, please see their website.
The Flag 4 GP Registration data can be accessed within the Local Area Migration Indicators from the ONS website.
Details of the policy governing the release of new data are available by visiting www.statisticsauthority.gov.uk/assessment/code-of-practice/index.html or from the Media Relations Office email: firstname.lastname@example.org
These National Statistics are produced to high professional standards and released according to the arrangements approved by the UK Statistics Authority.
|Pete Large||+44 (0)1329 444647||Migration Statistics Unit||Pete.Large@ons.gsi.gov.uk|