Local area migration indicators metadata

• All indicators have been updated with the latest data for 2015 and 2016 (Short-Term International Migration (STIM) has been updated with 2014 final and 2015 provisional data).

• Mid-year estimates include estimates for refugees for the first time.

• Local authorities now in order of code number rather than alphabetical.

• Births to non-UK born mothers supplied by Northern Ireland Statistics and Research Agency (NISRA) for Northern Ireland from 2008 onwards.

• “Edinburgh, City of” changed to “City of Edinburgh”.

• “Eilean Siar” changed to “Na h-Eileanan Siar”.

• “Vale of Glamorgan, The” changed to “Vale of Glamorgan”.

• “Scottish Borders, The” changed to “Scottish Borders”.

• “Anglesey, Isle of” changed to “Isle of Anglesey”.

• All Welsh local authorities now include the Welsh language name.

• Flag 4 (GP registration) data supplier changed from Health and Social Care Information Centre (HSCIC) to NHS Digital.

Definition

Figures presented show the number of long-term international or internal movement in the UK in the year to June.

Time period

Mid-years; 2005 to 2016.

Geography

Estimates are available at a national level for England, Wales, Scotland and Northern Ireland and for regions, counties, unitary authorities and local authorities within England and Wales; council areas within Scotland; and local government districts within Northern Ireland.

Data sources

Office for National Statistics (ONS), National Records of Scotland (NRS) and Northern Ireland Statistics and Research Agency (NISRA).

Relevant definitions

Resident population

The estimated resident population of an area includes all people who usually live there, whatever their nationality. Members of UK and non-UK armed forces stationed in the UK are included and UK forces stationed outside the UK are excluded. Students are taken to be resident at their term-time address.

Long-Term International Migration (LTIM)

The methodology used to update the population estimates accounts for flows of long-term international migrants. The UN recommendation for defining a long-term international migrant is used:

“A person who moves to a country other than that of his or her usual residence for a period of at least a year, so that the country of destination effectively becomes his or her new country of usual residence.”

Inflow:
Persons arriving or returning from abroad to take up residence in a country for a period of at least 12 months.

Outflow:
Persons leaving their country of usual residence to take up residence in another country for a period of at least 12 months.

Internal migration (within UK)

Since internal moves are not recorded formally, information obtained from the NHS Central Register (NHSCR) and GP patient registers are used as a proxy for England and Wales estimates. These data are considered to be a good proxy for internal migration as, when moving, most patients will eventually register with a new GP. Complete information on all moves at former health authority level from the NHSCR are combined with more geographically-detailed data from the patient registers to produce the migration estimates by local authority. Higher Education Statistics Agency (HESA) administrative data is used within the production of internal migration estimates, primarily to improve the quality of estimating internal migration moves made by students.

Separate Scottish NHSCR information from the NHSCR and Community Health Index (CHI) are used to estimate internal migration for Scotland.

Information from the Health and Social Care Business Services Organisation (BSO) is used to estimate internal migration for Northern Ireland.

Notes on data:

International migration figures for England and Wales are taken from the components of change used in the mid-year population estimates and will differ from the official estimates of Long-Term International Migration (LTIM) – see Table MYE3.

Internal migration figures for local and unitary authorities in England and Wales are based on the components of change used in the mid-year population estimates; these may differ slightly from the official series of internal migration estimates, because of rounding during processing. There may also be instances of small differences at region and country level.

Internal and international migration estimates for local authorities in Northern Ireland 2005 to 2016 presented in this release are consistently specified with these components for other parts of the UK. These differ from the components of change used in the mid-year population estimates, which include flows to and from other parts of the UK as part of international migration rather than as part of internal migration.

Internal migration figures for Scotland 2005 to 2016 and all other parts of the UK for 2016 are taken from the mid-year population estimates.

Internal migration into and out of higher level areas is not the sum of numbers moving into or out of component lower level areas, as some migrants move between lower level areas as well.

Comparability

Migration flow figures are for mid-year to mid-year periods. Therefore reference periods are not directly comparable with other available indicators available on a calendar year basis.

Migration flow figures incorporate both inflows and outflows, and are therefore not directly comparable with administrative data sources, which record inflows only.

Population turnover rates are not directly comparable for different geographies, that is, smaller areas are more likely to have a higher turnover.

Data quality

The population estimates methodology guide for England and Wales, including information on data quality, is available.

An equivalent methodology guide for Scotland is also available.

Quality and Methodology Information (QMI) for mid-year population estimates.

Quality and Methodology Information (QMI) for internal migration estimates.

A comparison of data sources and methods used to compile population estimates for local authorities across UK countries is available.

The ONS international migration methodology guide.

Information on the migration methodology used by NRS.

A combined population and migration methodology paper for Northern Ireland.

Further information

England and Wales population estimates.

For more information please contact ONS at: pop.info@ons.gov.uk

England and Wales internal migration data.

There is no formal registration of internal migration moves so within England and Wales estimates are derived from NHS data, on the basis that most people register with a new GP when they move. Data from the Higher Education Statistics Agency (HESA) are also used to improve estimation of moves for and after study. This combination is considered to provide a good proxy for actual moves. Full information on the methods is in the Quality and Methodology Information report.

For more information please contact ONS at: migstatsunit@ons.gov.uk

UK Long-Term International Migration (LTIM) estimates

Scotland population and migration estimates.

For more information please contact NRS at: statisticscustomerservices@nrscotland.gov.uk

Northern Ireland population and migration estimates.

For more information please contact NISRA at: census@nisra.gov.uk

Definition

Figures presented show the estimates of short-term international migrants who stayed in England and Wales (in the year to June) per 1,000 resident population.

Time period

Mid-years; 2008 to 2015 (provisional).

Geography

Estimates are available at a national level for England and Wales and regions, counties, unitary authorities and local authorities within England and Wales.

Data sources

The International Passenger Survey (IPS) carried out by Office for National Statistics (ONS) is the primary source of Short-Term International Migration data. It is used to create a single estimate of the short-term migration inflow to England and Wales, which is then distributed to local authority level using the following administrative data sources:

• grants of extensions of Leave to Remain from Home Office

• Certificates of Sponsorship (CoS) from Home Office

• Confirmation of Acceptance to Study (CAS) from Home Office

• Migrant Workers Scan (MWS) from Department for Work and Pensions (DWP)

• Student Record from Higher Education Statistics Agency (HESA)

• Individualised Learner Record from Department for Business, Energy and Industrial Strategy (BEIS)

• Lifelong Learning Wales Record from Welsh Government (WG)

Resident population

The estimated resident population of an area includes all people who usually live there for more than 12 months, whatever their nationality. Members of UK and non-UK armed forces stationed in the UK are included and UK forces stationed outside the UK are excluded. Students are taken to be resident at their term-time address.

Short-term international inflow

The UN definition of a short-term international migrant is used:

"A person who moves to a country other than that of his or her usual residence for a period of at least 3 months but less than a year (12 months) except in cases where the movement to that country is for purposes of recreation, holiday, visits to friends and relatives, business, medical treatment or religious pilgrimage".

Notes on data

Short-term migration estimates are based upon estimates for short-term international immigration to England and Wales from outside the UK.

Immigrants who have spent time in England and Wales and in the rest of the UK are only included if they spent most of their time in England and Wales.

Estimates are based upon information collected by the IPS at the end of a visit (when a short-term immigrant leaves the UK). Information collected is therefore about actual behaviour.

Comparability

The method for producing STIM estimates at local authority level is based on the same theory as the methodology developed for long-term immigration estimates at local authority level. However, they cannot be added together to provide one single measure of international migration. Adding together Long-Term International Migration (LTIM) and STIM estimates does not provide a reliable measure of all immigration to the UK within a specific time period. Short-term immigration flows are based on journeys, not people, and have methodological differences from LTIM flows.

In addition, it is possible for someone to be both a long-term and short-term migrant in the same period, and STIM estimates are based on actual flows whereas LTIM covers migrants' intentions. However, although they cannot be added together to provide one single measure of international migration, LTIM and STIM estimates of immigration and emigration should be considered alongside and in the context of each other. These estimates represent different people migrating for different reasons but they can help to provide an overall picture of international migration.

Data quality

Local authority level estimates are provided to the nearest unit to enable and encourage further calculations and analysis. However, the estimates must not be assumed to be as exact as the level of detail implied by unit level data.

The individual local authority estimates are derived from overall flow estimates for England and Wales, which are sample survey-based and which have quite large confidence intervals. Please see Table STIM.01c ("Flows by main reason for migration - migrants satisfying UN definition of a short-term migrant") in the Short-Term International Migration Annual Report for the total inflow estimates and their associated confidence intervals.

In addition, England and Wales totals may not match national level published tables because local authority level estimates refer to moves made to the UK for 3 to 12 months for purposes of employment and study by non-British citizens only.

The methodology employed to derive estimates of short-term international migration is available.

Quality and Methodology Information (QMI) for Short-Term International Migration estimates.

Further information

The Short-Term International Migration Annual Report and its accompanying tables (including Table STIM.01c) is available.

For more information please contact: migstatsunit@ons.gov.uk

Definition

Figures presented show the estimated non-UK born population living in the UK in a calendar year per 1,000 Annual Population Survey (APS) resident population.

Time period

Calendar years; 2005 to 2016.

Geography

Estimates are available at a national level for England, Wales, Scotland and Northern Ireland and for regions, counties, unitary authorities and local authorities within England and Wales; and council areas within Scotland.

Data sources

APS, which is the Labour Force Survey (LFS) plus various sample boosts - Office for National Statistics (ONS).

Relevant definitions

Resident population - APS

The estimated resident population of an area includes all people who usually live there, whatever their country of birth or nationality. Members of UK and non-UK armed forces stationed in the UK are included and UK forces stationed outside the UK are excluded. Students are taken to be resident at their term-time address.

APS

The APS combines the results from the LFS Waves 1 and 5 with the English, Welsh and Scottish Local Labour Force Survey (LLFS). The sample size is 122,000 households (or 320,000 respondents) on the annual APS dataset, compared with 40,000 households (or 120,000 respondents) on the quarterly LFS dataset. For 2004 and 2005, the APS also comprised a boost sample (APS(B)) of 65,000 households. However, APS(B) ceased at the end of December 2005.

Notes on data

The APS was reweighted in 2015 in line with the results of the 2011 Census. The data for calendar years 2004 to 2013 has been revised in the light of that reweighting exercise.

The APS has the largest coverage of any household survey and can thus generate statistics for small geographical areas.

APS coverage omits communal establishments, except NHS housing and students in halls of residence with a UK resident parent.

Members of the armed forces are only included if they live in private accommodation.

All residents born outside the UK are included in the APS regardless of the length of time they have been resident, providing they consider the sampled address to be their main residence.

The population figures used to weight the APS are not the same as the mid-year population estimates. APS population figures are based on population projections adjusted for private households. Further information can be found in the LFS user guide.

Comparability

Estimates of non-UK born population from the APS provide an indication of migration stocks, therefore this indicator is not directly comparable with indicators of migration flows such as population turnover or National Insurance number (NINo) registrations.

Data quality

Quality and Methodology Information (QMI) for the APS is available.

Further information

APS data are also available from Nomis.

The LFS user guide.

Population by country of birth and nationality published tables (2000 onwards).

Underlying datasets. These include more detailed breakdowns but do not cover Scottish council areas.

For more information please contact: migstatsunit@ons.gov.uk

Definition

Figures presented show the estimated population of non-British nationality living in the UK in a calendar year per 1,000 Annual Population Survey (APS) resident population.

Time period

Calendar years; 2005 to 2016.

Geography

Estimates are available at a national level for England, Wales, Scotland and Northern Ireland and for regions, counties, unitary authorities and local authorities within England and Wales; and council areas within Scotland.

Data sources

APS, which is the Labour Force Survey (LFS) plus various sample boosts - Office for National Statistics (ONS).

Relevant definitions

Resident population - APS

The estimated resident population of an area includes all people who usually live there, whatever their country of birth or nationality. Members of UK and non-UK armed forces stationed in the UK are included and UK forces stationed outside the UK are excluded. Students are taken to be resident at their term-time address.

APS

The APS combines the results from the LFS Waves 1 and 5 with the English, Welsh and Scottish Local Labour Force Survey (LLFS). The sample size is 122,000 households (or 320,000 respondents) on the annual APS dataset, compared with 40,000 households (or 120,000 respondents) on the quarterly LFS dataset. For 2004 and 2005, the APS also comprised a boost sample (APS(B)) of 65,000 households. However, APS(B) ceased at the end of December 2005.

Citizenship

Citizenship is defined as the nationality of the passport which the traveller is carrying. Where more than one passport is held, citizenship is determined by the respondent.

The British Nationality Act 1981, which came into force on 1 January 1983, replaced citizenship of the UK and colonies with British citizenship, British Overseas citizenship and British Dependent Territories citizenship. British Overseas citizens are recorded as New Commonwealth citizens, instead of as British citizens. Persons with British Overseas Territories citizenship are shown under the country that issued their passport. Citizens of Gibraltar are recorded as British citizens.

Notes on data

The APS was reweighted in 2015 in line with the results of the 2011 Census. The data for calendar years 2004 to 2013 has been revised in the light of that reweighting exercise.

The APS has the largest coverage of any household survey and can thus generate statistics for small geographical areas.

APS coverage omits communal establishments, except NHS housing and students in halls of residence with a UK resident parent.

Members of the armed forces are only included if they live in private accommodation.

All residents born outside the UK are included in the APS regardless of the length of time they have been resident, providing they consider the sampled address to be their main residence.

The population figures used to weight the APS are not the same as the mid-year population estimates. APS population figures are based on population projections adjusted for private households. Further information can be found in the LFS user guide.

Comparability

Estimates of non-British citizens from the APS provide an indication of migration stocks, therefore this indicator is not directly comparable with indicators of migration flows such as population turnover or National Insurance number (NINo) registrations.

Data quality

Quality and Methodology Information (QMI) for the APS is available.

Further information

APS data are also available from Nomis.

The LFS user guide.

Population by country of birth and nationality published tables (2000 onwards).

Underlying datasets. These include more detailed breakdowns but do not cover Scottish council areas.

For more information please contact: migstatsunit@ons.gov.uk

Definition

Figures presented show the number of NINo allocations to adult overseas nationals entering the UK per 1,000 resident population aged 16 to 64 by calendar year.

Time period

Calendar years; 2005 to 2016.

Geography

Data are available at a national level for England, Wales, Scotland and Northern Ireland and for regions, counties, unitary authorities and local authorities within England and Wales; council areas within Scotland; and local government districts within Northern Ireland.

English county level data are aggregated from the published local authority data.

Data sources

National Insurance number allocations - Department for Work and Pensions (DWP).

Relevant definitions

Resident population

The estimated resident population of an area includes all people aged 16 to 64 who usually live there, whatever their nationality. Members of UK and non-UK armed forces stationed in the UK are included and UK forces stationed outside the UK are excluded. Students are taken to be resident at their term-time address.

The methodology used to update the population estimates accounts for flows of long-term international migrants. A long-term international migrant is defined as somebody who changes his or her country of usual residence for a period of at least 1 year.

Notes on data

There may be a considerable delay between arrival and registering for a NINo.

There is no minimum stay requirement for registration.

Only migrants over 16 years of age, planning to work or claim benefits are covered.

No information on outflows is available.

Data include migrants from the Republic of Ireland.

Asylum seekers are not eligible to register for a NINo until their case has been approved.

Data is based on date of registration, not date of arrival.

NINo data reflect a migrant’s first destination or location at registration, they do not reflect the stock of migrants nationally or where they may settle.

Comparability

Administrative sources are not primarily designed for statistical purposes. The coverage of international migrants joining an administrative source will depend on the purpose of the particular administrative system and will invariably differ between sources. They will cover both short- and long-term migrants.

There is no minimum stay requirement to register for a NINo, compared with 12 months for the population turnover figures. Coverage is also limited to the population eligible to work or claim benefits. This indicator is therefore not directly comparable with other migration indicators.

Data quality

100% administrative data. Data is released quarterly with a lead time of 3 months, that is, data released in August 2016 covers NINo registrations to June 2016.

Further information

NINo data.

Definition

Figures presented show the number of new Flag 4 records added in the previous 12 months existing on the patient register as at 31 July for England and Wales (also shown as per 1,000 resident population). Equivalent figures (Code 4) are provided for Northern Ireland.

Time period

Mid-years (31 July); 2005 to 2016 (to mid-2015 for Northern Ireland).

Geography

Data are available at a national level for England, Wales and Northern Ireland and for regions, counties, unitary authorities and local authorities within England and Wales; and local government districts within Northern Ireland.

English region, county and unitary authority level data are aggregated from the published local authority data.

Data for Scotland are unavailable as non-UK nationals cannot be identified within the NHS sources supplied.

Data sources

Flag 4 records are produced as part of the Patient Register Data Service (PRDS) held by NHS Digital (formerly held by Health and Social Care Information Centre (HSCIC)) and provided to Office for National Statistics (ONS).

Code 4 records are provided to Northern Ireland Statistics and Research Agency (NISRA) by the Health and Social Care Business Services Organisation (BSO).

Relevant definitions

Resident population

The estimated resident population of an area includes all people who usually live there, whatever their nationality. Members of UK and non-UK armed forces stationed in the UK are included and UK forces stationed outside the UK are excluded. Students are taken to be resident at their term-time address.

The methodology used to update the population estimates accounts for flows of long-term international migrants. A long-term international migrant is defined as somebody who changes his or her country of usual residence for a period of at least 1 year.

Flag 4

Flag 4s are codes within the PRDS system that indicate that someone who has registered with a GP in England and Wales was previously living overseas.

A Flag 4 may be generated when an individual registers with an NHS GP if:

• an individual was born outside the UK and enters England and Wales for the first time and registers with a NHS GP

• an individual’s registration will also generate a Flag 4 if the previous address of an individual is reported as outside the UK

Code 4

Code 4s relate to individual registrations with a GP in Northern Ireland from persons who were previously living overseas. A Code 4 may be generated when an individual registers with a NHS GP if:

• an individual was born outside the UK and enters Northern Ireland for the first time and registers with a NHS GP

• an individual’s registration may also generate a Code 4 if their previous address is outside the UK and they have been living outside the UK for more than 1 year

Notes on data

Flag 4:

These data are designated as “Official statistics not designated as National Statistics”.

These data must be sourced to ONS.

Comparability

Migrant GP registration statistics provide an indication of recent international in-migrants to local authority areas; however, due to the following definitional differences the figures are not directly comparable with other indicators of migration such as estimates of long-term international migration.

Migrant GP registration statistics are derived from administrative systems that are not designed primarily for statistical purposes. For more information on internal migration estimates please see the Internal migration estimates Quality and Methodology Information report..

Flag 4 records may not be retained on patient register records through the person's subsequent migration within the UK. The patient register is a “snapshot” taken annually. When an in-migrant subsequently moves internally within the UK and re-registers with a second GP, the Flag 4 demarcation is not retained as the individual’s last residence is now within the UK. If this internal migration occurs within the year of in-migration, that is, before the next mid-year snapshot, the in-migration will not be recorded.

However, Northern Ireland still hold data for all migrants; due to the land border with the rest of Ireland, BSO assess the right to entitlement for all patients registering, even if they are migrants registered elsewhere in the UK first.

GP registration is not compulsory. Some migrants will only register with a GP if, and when, they require medical attention. There may also be a lag between the migration event and the eventual GP registration.

The completeness of the data depends on all patients registering with an NHS GP when they move to England and Wales or Northern Ireland. However, it is known that registration patterns vary by sex and age group. Therefore, the usefulness of the data as an indicator of migration is limited by some groups being less likely to register with a GP than others. For example, young men (who make up a large proportion of migrants) are less likely to register with a GP than other groups.

Data quality

Migrant GP registration data are based on administrative data sources, which are not designed for capturing information directly about migrants. However, using GP data, an indication of in-migration to local authorities may be derived. See previous for issues regarding comparability with other sources.

Further information

For any queries regarding Flag 4 data please email the migstatsunit@ons.gov.uk.

Definition

Birth statistics for England and Wales are based on the details collected when births are registered. By law, births should be registered within 42 days. The country of birth of parents for children born has been recorded at birth registration since April 1969.

Time period

2005 to 2016.

Geography

Birth statistics are available at a national level for England, Wales and Scotland, and regions, counties, unitary authorities and local authorities within England and Wales. As of 2017 are available for Northern Ireland.

Data sources

Birth registration data.

Relevant definitions

Birth statistics for England and Wales are based on the details collected when births are registered.

The area refers to the area of usual residence of the mother.

The country of birth of each parent for children born in England and Wales has been recorded at birth registration since April 1969. This is coded to country of birth for statistical purposes. The details for country of birth groupings can be found in the Parents’ country of birth package on the metadata tab. Birthplace does not necessarily equate with ethnic group. A fuller discussion of this subject can be found in a Population Trends article.

Notes on data:

Live births to UK born mothers and non-UK born mothers do not sum to total live births because a small number of records do not have mother's country of birth stated.

Birth statistics for England and Wales are based on the details collected when births are registered. By law, births should be registered within 42 days. The country of birth of parents for children born has been recorded at birth registration since April 1969.

Country of birth of mother is used for this analysis since this information is collected at birth registration, unlike ethnicity or migration history. Care is needed in interpretation as country of birth should not be used as a proxy for these variables. For example, not all women born outside the UK will be recent in-migrants. Similarly, the UK born will include the children of earlier in-migrants (the second and third generation).

To preserve confidentiality, counts for Isles of Scilly have been combined with Cornwall.

Live births to UK born mothers and non-UK born mothers do not sum to total live births because a small number of records do not have mother's country of birth stated. In 2016, there were 43 records where the mother's country of birth was not stated.

Comparability

Not applicable.

Data quality

Quality and Methodology Information and metadata are linked in the Further information section.

Further information

Release - Total live births in Scotland.

Births information for Northern Ireland.

Telephone: +44 (0)2890 388492

Release - Parents' country of birth, England and Wales, 2015.

England and Wales Births user guide.

England and Wales Births Quality and Methodology Information.

Births information for England and Wales:
Vital Statistics Outputs Branch
vsob@ons.gov.uk
Telephone: +44 (0)1329 444110