Reference metadata describe statistical concepts and methodologies used for the collection and generation of data. They provide information on data quality and, since they are strongly content-oriented, assist users in interpreting the data. Reference metadata, unlike structural metadata, can be decoupled from the data.
Data and metadata are transmitted to Eurostat by the Member States in the framework of the Unified Demographic Data Collection which is in accordance with Regulation (EC) No 862/2007 and Regulation (EU) No 1260/2013 and their implementing regulations.
The current regional breakdown of the countries in the regional demographic tables is according to:
1. Regulation (EU) 2016/2066 amending the annexes to Regulation (EC) No 1059/2003 of the European Parliament and of the Council on the establishment of a common classification of territorial units for statistics (NUTS). The NUTS classification according to this regulation is shortly named NUTS-2016.
2. Agreements between Eurostat and Candidate countries as well as between Eurostat and EFTA countries, for which statistical regions have been coded in a way that resembles NUTS.
3.3. Coverage - sector
A time series for population estimates is available back to the following dates:
Total UK: 1851;
Quinary age and sex: 1953;
Single year of age and sex: 1971;
A time series for the number of births and deaths is available back to 1887;
A time series for migration data is available back to 1975.
3.4. Statistical concepts and definitions
3.4.1 Statistical concepts and definitions used in the statistics transmitted to Eurostat
1.Usually Resident Population
2. Legal Residence Population
3. Registered Residence Population
4. Other
Population
Usual Resident Population.
None.
Live births
Live births are all births that occur and are then registered in the UK to usual residents. Births to UK residents which are registered outside the UK and births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded. Births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (220 in 2017).
Deaths
Deaths are all deaths that occur and are then registered in the UK to usual residents. Deaths to UK residents which are registered outside the UK are excluded. Deaths that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 446 in 2017).
Immigrants
A person arriving or returning from abroad to take up residence in a country for a period of at least 12 months. This is in line with the UN definition.
Emigrants
A person who leaves their country of usual residence to take up residence in another country for a period of at least 12 months. This is in line with the UN definition.
Acquisitions of citizenship
The definition of citizenship is as stated in Article.9.3 of Regulation (EC) No 862/2007.
Loss of citizenship
The definition of citizenship is as stated in Article 9.3 of Regulation (EC) No 862/2007.
Legally induced abortions
Legal abortions data does not include abortions to non-residents of England, Wales or Scotland.
Late foetal deaths
Stillbirths are all stillbirths that occur and are then registered in the UK to usual residents. Stillbirths to UK residents which are registered outside the UK are excluded.
Infant deaths
Infant deaths are all infant deaths that occur and are then registered in the UK to usual residents. Infant deaths to UK residents which are registered outside the UK are excluded.
Marriages
Marriages are all marriages that took place in the UK. The statistics do not include marriages to residents of UK that took place abroad, but do include marriages that took place in UK to non-residents.
Divorces
Divorces are all divorces that took place in UK following court orders. The statistics do not include divorces to couples usually resident in UK that took place abroad.
3.4.2 Statistical concepts and definitions used in the statistics disseminated in the National Statistical Institute's website
Population
Population estimates use the usual residence definition.
Live births
Births that occur and are then registered in the UK to usual residents. Births to UK residents which are registered outside the UK are excluded. Births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 220 in 2017). Figures for England and Wales are based on births occurring in a calendar year. Figures for Scotland and Northern Ireland are based on births registered in a calendar year.
Deaths
Deaths that occur and are then registered in the UK to usual residents. Deaths to UK residents which are registered outside the UK are excluded. Deaths that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 446 in 2017). Figures are based on deaths registered in a calendar year.
Immigrants
‘Immigration’ means the action by which a person establishes his or her usual residence in the territory of a Member State for a period that is, or is expected to be, of at least 12 months, having previously been usually resident in another Member State or a third country.
Emigrants
‘Emigration’ means the action by which a person, having previously been usually resident in the territory of a Member State, ceases to have his or her usual residence in that Member State for a period that is, or is expected to be, of at least 12 months.
Acquisitions of citizenship
The definition of citizenship is as stated in Article 9.3 of Regulation (EC) No 862/2007.
Loss of citizenship
The definition of citizenship is as stated in Article 9.3 of Regulation (EC) No 862/2007.
Legally induced abortions
A legally induced abortion is a termination of a pregnancy by abortion under the 1967 Act, as amended by the Human Fertilisation and Embryology Act 1990.
A legally induced abortion must be certified by two registered medical practitioners as justified under one or more of the following grounds:
— the continuance of the pregnancy would involve risk to the life of the pregnant woman greater than if the pregnancy were terminated (Abortion Act, 1967 as amended, section 1(1)(c));
— the termination is necessary to prevent grave permanent injury to the physical or mental health of the pregnant woman (section 1(1)(b));
— the pregnancy has not exceeded its twenty-fourth week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of the pregnant woman (section 1(1)(a));
— the pregnancy has not exceeded its twenty-fourth week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of any existing children of the family of the pregnant woman (section 1(1)(a));
— there is a substantial risk that if the child were born it would suffer from such physical or mental abnormalities as to be seriously handicapped (section 1(1)(d));
or, in an emergency, certified by the operating practitioner as immediately necessary:
— to save the life of the pregnant woman (section 1(4));
— to prevent grave permanent injury to the physical or mental health of the pregnant woman (section 1(4)).
Late foetal deaths
The Stillbirth (Definition) Act 1992 defines a stillbirth as:
“A child that has issued forth from its mother after the 24th week of pregnancy, and that did not at any time after being completely expelled from its mother breathe or show any signs of life”.
This definition has been in use since 1 October 1992. Prior to this, the Births and Deaths Registration Act 1953 defined a stillbirth as above, but at 28 or more weeks completed gestation.
Infant deaths
Deaths under 1 year of age.
Marriages
Annual marriage statistics for the UK and its constituent countries are based on the details collected when marriages are solemnised, the statistics are based on information recorded in the marriage register.
Figures for the UK, England and Wales, Scotland and Northern Ireland represent the number of marriages solemnised in a particular year in either a civil or a religious ceremony. Figures are derived from information collected as part of the marriage registration process.
Marriage figures are based on country of formation and not country of residence and relate only to marriages taking place in the constituent countries of the UK. They do not include marriages of UK residents taking place abroad, but do include non UK residents who marry within the UK. There is no legal requirement for UK residents who get married abroad to register their marriage with UK authorities.
Divorces
Annual divorce statistics for the UK and its constituent countries are based on information recorded when decrees are made absolute and decrees of nullity are given. Figures are derived from forms supplied by the courts. Figures for the UK, England and Wales, Scotland and Northern Ireland represent the number of marriages dissolved or annulled in a particular year (based on the date the decree absolute or decree of nullity was awarded). Figures are based on country of dissolution and not country of residence.
3.4.3 Differences in statistical concepts and definitions between the statistics transmitted to Eurostat and those disseminated in the National Statistics Institute's website
Population
None – the Usual Residence definition is used.
Population estimates refer to the usually resident population. This can mean that estimates of population do not necessarily coincide with the number of people to be found in an area at a particular time of the day or year.
For most people, defining where they usually live for the purposes of the census for example, is quite straightforward. For a minority of people the concept of usual residence is however more difficult to define, for example for students, members of the armed forces, prisoners and international migrants.
Specific rules are used for these groups:
— Higher education students and school children studying away from home are resident at their term-time address.
— Members of the armed forces are usually resident at the address where they spend most of their time.
— Prisoners are usually resident in the prison estate if they have a sentence of six months or more.
— International migrants are usually resident if they intend to stay in England and Wales for more then 12 months.
Live births
Live births are all births that occur and are then registered in the UK to usual residents. Births to UK residents which are registered outside the UK are excluded. Also Births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 220 in 2017). Figures for England and Wales are based on births occurring in a calendar year. Figures for Scotland and Northern Ireland are based on births registered in a calendar year. The difference between providing wholly birth registration data for the UK in comparison to birth registration data for Scotland and Northern Ireland combined with birth occurrence data for England and Wales varied between 0.001 % and 0.43 % during the period 2006 to 2016 (between 10 and 3 400 births per year).
It should be noted that in England and Wales where a birth is registered too late to be included in the count for the year of occurrence, it will be included in the count for the following year. There are some births registered too late for this also but the numbers are low.
Deaths
Deaths are all deaths that occur and are then registered in the UK to usual residents. Deaths to UK residents which are registered outside the UK are excluded. Deaths that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (less than 450 in 2017).
Figures are based on deaths registered in a calendar year.
Looking at England and Wales data for death registrations and death occurrences, the difference between the total death figures for a reference year varied between 0.01 % and 1.2 % during the period 2006 to 2016 (between 30 and 6 300 deaths per year). For Scotland, this varied between 0.0 % and 0.4 % during the period 2006 to 2016 (between 1 and 248 deaths per year).
It should be noted that death occurrence figures are extracted at a particular point in time in England and Wales, 10 months after the end of the calendar year. There will be more deaths registered after this point in time which will not be included within any death occurrence dataset. For example, there are currently between 1 700 and 3 800 deaths per year that are not included in England and Wales death occurrence datasets for the calendar years 2006 to 2016 (as of March 2018). Thus, death registration data provides a more complete time series of data. In Scotland and Northern Ireland, a death occurrence dataset is not routinely extracted so death occurrence figures will vary over time depending on when the data is extracted.
It should be noted that deaths registered in a reference year will include some deaths that occurred in previous year. For example, in the England and Wales, 5 % of deaths registered in 2017 were from previous years (around 27 800 deaths).
The deaths not included in the registration file are likely to be a mix of those deaths registered in early January for deaths in late December and those deaths referred to a coroner (or Procurators Fiscal in Scotland) ie those considered unexpected, accidental or suspicious.
The number of deaths to UK residents which are registered outside the UK is likely to be very small so has a negligible impact on statistics.
Immigrants
None.
Emigrants
None.
Acquisitions of citizenship
None.
Loss of citizenship
None.
Legally induced abortions
Not applicable.
Late foetal deaths
Stillbirths are all stillbirths that occur and are then registered in the UK to usual residents. Stillbirths to UK residents which are registered outside the UK are excluded
Figures for England and Wales are based on stillbirths occurring in a calendar year. Figures for Scotland and Northern Ireland are based on stillbirths registered in a calendar year. It should be noted that in England and Wales where a stillbirth is registered too late to be included in the count for the year of occurrence, it will be included in the count for the following year. The number of these is very small.
Infant deaths
Infant deaths are all infant deaths that occur and are then registered in the UK to usual residents. Infant deaths to UK residents which are registered outside the UK are excluded.
Figures are based on infant deaths registered in a calendar year. The infant deaths not included in the registration file are likely to be a mix of those infant deaths registered in early January for deaths in late December and those infant deaths referred to a coroner (or Procurators Fiscal in Scotland) ie those considered unexpected, accidental or suspicious.
It should be noted that infant deaths registered in a reference year will include some infant deaths that occurred in the previous year.
The number of infant deaths to UK residents which are registered outside the UK is likely to be very small so has a negligible impact on statistics.
Marriages
Marriages are all marriages that took place in the UK. Therefore the statistics do not include marriages to residents of UK that took place abroad and they do include marriages that took place in UK to non-residents.
Divorces
Divorces are all divorces that took place in UK following court orders. Therefore the statistics do not include divorces to couples usually resident in UK that took place abroad.
3.5. Statistical unit
Number of persons.
3.6. Statistical population
Statistical population
Population
Usually resident population.
Live births
Not available.
Deaths
Not available.
Immigrants
The principal data source is the International Passenger Survey. The target statistical population is all travellers entering or leaving the UK through air and sea ports and the Channel Tunnel. The survey covers 95 % of travellers entering and leaving the UK.
Emigrants
The principal data source is the International Passenger Survey. The target statistical population is all travellers entering or leaving the UK through air and sea ports and the Channel Tunnel. The survey covers 95 % of travellers entering and leaving the UK.
Acquisitions of citizenship
Those that are acquiring British citizenship through application, based on a residence of 3 years for someone whose spouse or civil partner is British and 5 years for others.
Loss of citizenship
Under the British Nationality Act 1981 it is possible for British citizens who are over 18 years of age and of full capacity to apply to renounce their nationality, although renunciation will only be granted where that applicant already has or is about to acquire citizenship of another country. Further information on renunciation of British citizenship is available on the Home Office website: https://www.gov.uk/renounce-british-nationality.
Legally induced abortions
Not available.
Late foetal deaths
Not available.
Infant deaths
Not available.
Marriages
Not available.
Divorces
Not available.
3.7. Reference area
Population, live births and deaths data are available at national and regional level of geographical detail.
3.8. Coverage - Time
Population estimates data with the reference 31 December/1 January is available from 2001. Alternative series for population estimates based on the mid-year reference point is available back to the following dates:
Total UK: 1851;
Quinary age and sex: 1953;
Single year of age and sex: 1971;
A time series for the number of births and deaths is available back to 1887;
A time series for migration data is available back to 1975.
3.9. Base period
Not applicable.
Data is collected at unit (person) level.
The reference date for population data is the end of the reference period (midnight of 31 December). The reference period for vital and dual events data is the calendar year in which the events occurred. The reference period for migration flow data is the calendar year in which the migration occurred.
6.1. Institutional Mandate - legal acts and other agreements
Regulation (EC) No 862/2007.
6.2. Institutional Mandate - data sharing
Regulation (EC) No 862/2007.
7.1. Confidentiality - policy
Disclosure control guidance for birth and death statistics for England and Wales can be found on ONS website at:
The population estimates are produced using a variety of data sources and statistical models, including some statistical disclosure control methods, and small estimates should not be taken to refer to individuals.
7.2. Confidentiality - data treatment
To protect confidentiality in Table B02, data for mothers aged 14 and aged under 14 has been combined with data for mothers aged 15 born in 1998. Similarly, in Table B03, data for mothers aged under 15 has been combined with data for mothers aged 15-19.
For population estimates small estimates should not be taken to refer to individuals to protect confidentiality in Table B02, data for mothers aged 14 and under has been combined with data for mothers aged 15 born in 1998. Similarly in Table B03, data for mothers aged under 15 has been combined with data for mothers aged 15-19.
For population estimates small estimates should not be taken to refer to particular individuals.
8.1. Release calendar
Population estimates to the mid-year reference point of the preceding year are published at the end of June. First release of births and deaths are published in June for Scotland, mid-July for England and Wales and July/August for Northern Ireland. Migration statistics are published quarterly in February, May, August and November.
In recent years there has been no news release for births and deaths data in England and Wales. In Scotland a news release for birth and death figures was released in June 2018:
Citizenship information is not collected when registering a birth or death in the UK. Therefore, an algorithm has been developed to estimate country of citizenship from country of birth for mothers giving birth and for deaths. This is based on 2011 Census information on the relationship between derived citizenship and country of birth by age group and sex.
Citizenship information for migration statistics is based on the passport on which the migrant is travelling.
Country of birth
Yes.
The following definition is used:
the country (in its current borders, if the information is available) in which the birth took place.
Country of birth of the mother
Yes.
Country of previous usual residence
Yes.
Country of next usual residence
Yes.
Deaths
Yes.
Divorce
Yes.
Emigrants
Yes.
First-time marrying person
Yes.
First-time registering partner
Yes.
Foetal death
Yes.
Foreign-born
Yes.
Immigrants
Yes.
Infant death
Yes.
Late foetal death
No, the definition in the UK is 24 weeks.
Legally induced abortions
Yes.
Level of development
Yes.
Live birth
Yes.
Live birth order
Yes.
Marriage
Yes.
Native born
Yes.
Person contracting legal union for first-time
Yes.
Regional
Yes.
Registered partnership
Yes.
Registered partnership legally dissolved
Yes.
Separation
Yes.
11.2. Quality management - assessment
11.2.1. Quality assessment: Type of duration of stay used when counting a person as a migrant according to Art. 2(b) of Regulation (EC) No 862/2007
1. Actual duration of stay of at least 12 months
2. Intended duration of stay of at least 12 months
3. Actual and intended duration of stay of at least 12 months
4. Other. Please specify
Nationals
Immigrants
Intended 12 month stay.
Emigrants
Intended 12 month stay.
EEA citizens
Immigrants
Intended 12 month stay.
Emigrants
Intended 12 month stay.
Non EEA citizens
Immigrants
Intended 12 month stay.
Emigrants
Intended 12 month stay.
11.2.2. Quality assessment of the definition of acquisitions of citizenship according to Art. 3(d) of Regulation (EC) No 862/2007
1. Acquisitions of citizenship granted to persons having their usual residence in the territory of the Member State
2.Other. Please specify
Acquisitions of citizenship
Complete, subject to caveats listed below:
Persons for whom it is not possible to calculate age due to incomplete data.
Some persons granted British citizenship outside the UK.
Persons granted British citizenship under section 5 of the British Citizenship Act 1981.
12.1. Relevance - User Needs
Users are a mixture of bodies from central government, local government, health service, academics, researchers, charities and the general public. Different users require varying levels of detail in terms of figures and commentary.
The population estimates are an important input for a wide number of economic and social statistics. Main users include central and local government and the health sector, where they are used for planning and monitoring service delivery, resource allocation and managing the economy. Additionally, they are used by a wider range of organisations such as commercial companies (for market research), special interest groups and academia as well as being of interest to the general public.
12.2. Relevance - User Satisfaction
Feedback is requested from users from each release of data and on emails to customers. In addition, ONS holds regular “key account” meetings with key user organisations to ensure that the quality and relevance of outputs is maintained.
12.3. Completeness
The statistics that are most needed are available.
Ad-hoc requests for data that are not routinely published are made available on the ONS website:
Overall accuracy and special cases (Inclusion/exclusion of asylum seekers and refugees, persons living on unauthorised or irregular basis, international students, persons who do not register/deregister,...)
Overall, the data quality for the total numbers of those granted and refused British citizenship is high. These data:
— are administrative counts of the Home Office’s casework processes, which are defined in UK legislation and are recorded under detailed categories on the Home Office’s administrative database;
— are scrutinised regularly as part of the performance monitoring of the Home Office;
— are regularly assessed as part of the Home Office’s Quality Assurance Framework;
— have not, in recent years, had to be altered significantly between initial provisional totals released in February each year and subsequent revised totals released in the following May and have not, in recent years, had to be revised at all when the annual data are subsequently checked 12 months later and the provisional status of the data is altered to final;
— do not require sampling processes for the compilation of the figures and hence have no associated sampling errors; and
— undergo a thorough reconciliation process including some data cleansing.
Loss of citizenship
Overall, the data quality for the total numbers of those granted and refused British citizenship is considered to be high. These data:
— are administrative counts of the Home Office’s casework processes, which are defined in UK legislation and are recorded under detailed categories on the Home Office’s administrative database;
— are scrutinised regularly as part of the performance monitoring of the Home Office;
— are regularly assessed as part of the Home Office’s Quality Assurance Framework;
— have not, in recent years, had to be altered significantly between initial provisional totals released in February each year and subsequent revised totals released in the following May and have not, in recent years, had to be revised at all when the annual data are subsequently checked 12 months later and the provisional status of the data is altered to final;
— do not require sampling processes for the compilation of the figures and hence have no associated sampling errors; and
— undergo a thorough reconciliation process including some data cleansing.
Legally induced abortions
Data quality and methods for abortions in England and Wales (Annex A)
IPS Immigration estimates are subject to sampling error and are published alongside confidence intervals to give user's an indication of the size of the error. Typically annual immigration is around 500 000 with a margin of error (representing the 95 % confidence interval) of +/- 30 000.
Estimates provided to Eurostat do not have confidence intervals attached.
Emigrants
IPS Emigration estimates are subject to sampling error and are published alongside confidence intervals to give user's an indication of the size of the error. Typically annual immigration is around 300 000 with a margin of error (representing the 95 % confidence interval) of +/- 20 000.
Estimates provided to Eurostat do not have confidence intervals attached.
There is no method for quantifying the error associated with the non-survey components of LTIM, which are unlikely to be random. Since the majority of the estimate is based on IPS data, LTIM estimates are published alongside IPS confidence intervals to give users an indication of the robustness of the estimate.
The confidence intervals do not take into account non-sampling error such as non-response bias and measurement error which cannot be quantified.
Non-response bias would be introduced if those who choose to respond to the survey have different characteristics to those who do not; or, if at peak times sampled passengers do not complete an IPS questionnaire because the number of interviewers is insufficient to cope with the high volume of passengers. The weighting applied to the estimates on total passenger flows will account for these non-contacts, but if their migration characteristics are different in some way then non-response bias would occur. Measurement error would be introduced, for example, if respondents provide incorrect information to the IPS interviewers.
Emigrants
There is no method for quantifying the error associated with the non-survey components of LTIM, which are unlikely to be random. Since the majority of the estimate is based on IPS data, LTIM estimates are published alongside IPS confidence intervals to give users an indication of the robustness of the estimate.
The confidence intervals do not take into account non-sampling error such as non-response bias and measurement error which cannot be quantified.
Non-response bias would be introduced if those who choose to respond to the survey have different characteristics to those who do not; or, if at peak times sampled passengers do not complete an IPS questionnaire because the number of interviewers is insufficient to cope with the high volume of passengers. The weighting applied to the estimates on total passenger flows will account for these non-contacts, but if their migration characteristics are different in some way then non-response bias would occur. Measurement error would be introduced, for example, if respondents provide incorrect information to the IPS interviewers.
Acquisitions of citizenship
Persons for whom it is not possible to calculate age due to incomplete data and persons granted British citizenship outside the UK.
Date of birth is not recorded in a small fraction of cases, leading to the inability to calculate age.
Loss of citizenship
Persons for whom it is not possible to calculate age due to incomplete data and persons granted British citizenship outside the UK.
Date of birth is not recorded in a small fraction of cases, leading to the inability to calculate age.
Legally induced abortions
Not applicable.
Late foetal deaths
Not applicable.
Infant deaths
Not applicable.
Marriages
Not applicable.
Divorces
Not applicable.
14.1. Timeliness
According to Art 4 (2) of the Commission Implementing Regulation (EU) No 205/2014, each year Member States shall provide the Commission (Eurostat) with data at national and regional level as described in Annex II and related standard reference metadata ( In the metadata structure definition defined for the Euro SDMX Metadata Structure) for the reference year within 12 months of the end of the reference year. According to Art 3 (2) of the Commission Regulation (EC) No 862/2007, Statistics on international migration, usually resident population and acquisition of citizenship shall be supplied to the Commission (Eurostat) within 12 months of the end of the reference year.
14.2. Punctuality
Estimates are delivered on time.
15.1. Comparability - geographical
For population estimates, although there are small differences in methods between the constituent countries of the UK, the estimates are stated to be comparable for areas within the UK. This is documented at:
Birth statistics for England and Wales are based on the number of births occurring in the year, while Scotland and Northern Ireland statistics relate to the number of births registered in the year. In England and Wales where a birth is registered too late to be included in the count for the year of occurrence, it will be included in the count for the following year. The differences between reporting occurrences and registrations are minor and figures are broadly comparable.
Death statistics are based on the number of deaths registered in the year across the UK so are comparable.
For migration, estimates are comparable across the UK countries.
15.2. Comparability - over time
Comparability - over time
Population
Definitions have remained consistent since 2002, and estimates from 2002-2017 are all based on both the 2001 and the 2011 Census, thus allowing comparison over time. Plans for revisions to methodology, and the publication of a back-series covering 2012-2017, are available at:
A time series for the number of births is available back to 1887. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Deaths
A time series for the number of deaths is available back to 1887. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Immigrants
LTIM – Available from 1991 to 2018 (final data).
Data supplied to Eurostat for 2008 to 2018 are comparable.
More information on changes and comparability over time:
The first reference year for which data are available is 1968.
Late foetal deaths
A time series for the number of stillbirths is available back to 1961 (when registration of stillbirths first came into operation). The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table. The definition of stillbirth changed from 28 or more weeks completed gestation to after 24th week of pregnancy in October 1992.
Infant deaths
A time series for the number of infant deaths is available back to 1900. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Marriages
A time series for the number of marriages is available back to 1862. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Divorces
A time series for the number of divorces is available back to 1971. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Surface in km2
15.3. Coherence - cross domain
PEU: Usual resident population used for all statistical population outputs. Some definitional differences in population used as denominators in surveys (e.g. Labour Force Survey uses usual resident household population as well as students and medical staff in communal establishments). Other surveys use only usual residents in private households.
VSOB: not available.
MSU: not available.
15.4. Coherence - internal
The current population estimates will be different from that calculated by applying the official births, deaths and migration figures to the previous year's estimates for the following reasons:
— Movements of (UK or other) Armed Forces into and out of the UK are counted separately and applied to the population estimates as an adjustment rather than through international migration.
— Births and deaths used in the population estimates are on an occurrence rather than a registration basis (the latter is the basis used in most deaths statistics across UK while births in Scotland and Northern Ireland are on a registration basis).
— The estimate of the international migration component of population change uses some provisional data and will thus be slightly different to the final official international migration estimates.
Differences in the application of the balancing equation applied since 1 January 2015 mean that these estimates do not correspond precisely with the change in population estimates used in the official national UK series of mid-year reference point estimates series.
Birth statistics are based on information collected when a birth is registered.
Deaths
Mortality statistics are based on the information collected when a death is registered.
Immigrants
Main data sources are:
International Passenger Survey (ONS);
Asylum seeker approvals (Home Office);
Northern Ireland Health card data (NISRA);
Labour Force Survey (ONS - calibration only);
Emigrants
Main data sources are:
International Passenger Survey (ONS);
Asylum seeker approvals (Home Office);
Northern Ireland Health card data (NISRA);
Labour Force Survey (ONS – calibration only).
Acquisitions of citizenship
UK Border Agency administrative data drawn from the Case Information Database.
Loss of citizenship
UK Border Agency administrative data drawn from the Case Information Database.
Legally induced abortions
Abortion notifications.
Late foetal deaths
Stillbirth registrations.
Infant deaths
Infant death statistics are based on the information collected when an infant death is registered.
Marriages
Marriage statistics are based on the information collected when a marriage is registered.
Divorces
Divorce statistics are based on the information collected by the court service.
Surface in km2
Not Applicable.
18.2. Frequency of data collection
Population estimates data are collected annually.
Data from birth and death registrations for England and Wales are provided on a daily basis to ONS. Births and deaths data from Scotland and Northern Ireland are provided on annual basis to ONS.
IPS data are collected on an ongoing basis and supplied for producing migration estimates on a quarterly basis.
Asylum seeker approvals and Health card data are supplied on a quarterly basis.
18.3. Data collection
Data collection is not carried out directly. Estimates of components of population change are received from other teams within ONS, and other government department. Births and deaths data is provided by register offices. Migration data is received from other teams within ONS, NISRA and the Home Office.
Births and deaths data is provided by register offices. Checks of completeness, allowable values, comparison with previous years and imputation is carried out where necessary.
Migration data is received from other teams within ONS, NISRA and the Home Office. Checks of completeness and allowable values are carried out and imputation applied where necessary.
18.5. Data compilation
Population Estimates are compiled by applying components of change to start-year population. Estimation of sex and age of migration data is made at local level. Estimation of place of usual residence is made at local level for armed forces based on 2011 Census results. Births and deaths data are coded, edited or imputed where necessary. Child deaths are linked with birth registrations using NHS number. For migration data, annual record editing is carried out where necessary. Some imputation of variables from best match donor within input stream in the quarter. Data processing and estimation occur within an internally developed computer system. Output reports are checked and include charts and logic to check balances produced. Totals in output spreadsheets are checked.
18.6. Adjustment
No statistical adjustment is carried out to adjust population definitions to standard definitions. At national level, the method of calculating 1 January populations from the mid-year populations calculated as standard is based on calendar year components of change (migration and natural change) as supplied in DEMOBAL data collection. This is the method for 1 January 2018 onwards.
These do not correspond precisely with the change in population estimates used in the official national UK series of mid-year reference point estimates series.
Note: For 1 January 2012-1 January 2017 we have adopted a slightly different method. We have used the average of two mid-year population estimates to represent the 1 January 20xx population. The statistical adjustment covers the difference between this figure and the net natural change to produce a national estimate of population (DEMOBAL).
Population estimates of the very old and centenarians (aged 90 to 110+) are based on the distribution of data both from the 2011 Census and other estimates of the very old produced at national level.
Not available.
Data and metadata are transmitted to Eurostat by the Member States in the framework of the Unified Demographic Data Collection which is in accordance with Regulation (EC) No 862/2007 and Regulation (EU) No 1260/2013 and their implementing regulations.
3.4.1 Statistical concepts and definitions used in the statistics transmitted to Eurostat
1.Usually Resident Population
2. Legal Residence Population
3. Registered Residence Population
4. Other
Population
Usual Resident Population.
None.
Live births
Live births are all births that occur and are then registered in the UK to usual residents. Births to UK residents which are registered outside the UK and births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded. Births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (220 in 2017).
Deaths
Deaths are all deaths that occur and are then registered in the UK to usual residents. Deaths to UK residents which are registered outside the UK are excluded. Deaths that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 446 in 2017).
Immigrants
A person arriving or returning from abroad to take up residence in a country for a period of at least 12 months. This is in line with the UN definition.
Emigrants
A person who leaves their country of usual residence to take up residence in another country for a period of at least 12 months. This is in line with the UN definition.
Acquisitions of citizenship
The definition of citizenship is as stated in Article.9.3 of Regulation (EC) No 862/2007.
Loss of citizenship
The definition of citizenship is as stated in Article 9.3 of Regulation (EC) No 862/2007.
Legally induced abortions
Legal abortions data does not include abortions to non-residents of England, Wales or Scotland.
Late foetal deaths
Stillbirths are all stillbirths that occur and are then registered in the UK to usual residents. Stillbirths to UK residents which are registered outside the UK are excluded.
Infant deaths
Infant deaths are all infant deaths that occur and are then registered in the UK to usual residents. Infant deaths to UK residents which are registered outside the UK are excluded.
Marriages
Marriages are all marriages that took place in the UK. The statistics do not include marriages to residents of UK that took place abroad, but do include marriages that took place in UK to non-residents.
Divorces
Divorces are all divorces that took place in UK following court orders. The statistics do not include divorces to couples usually resident in UK that took place abroad.
3.4.2 Statistical concepts and definitions used in the statistics disseminated in the National Statistical Institute's website
Population
Population estimates use the usual residence definition.
Live births
Births that occur and are then registered in the UK to usual residents. Births to UK residents which are registered outside the UK are excluded. Births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 220 in 2017). Figures for England and Wales are based on births occurring in a calendar year. Figures for Scotland and Northern Ireland are based on births registered in a calendar year.
Deaths
Deaths that occur and are then registered in the UK to usual residents. Deaths to UK residents which are registered outside the UK are excluded. Deaths that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 446 in 2017). Figures are based on deaths registered in a calendar year.
Immigrants
‘Immigration’ means the action by which a person establishes his or her usual residence in the territory of a Member State for a period that is, or is expected to be, of at least 12 months, having previously been usually resident in another Member State or a third country.
Emigrants
‘Emigration’ means the action by which a person, having previously been usually resident in the territory of a Member State, ceases to have his or her usual residence in that Member State for a period that is, or is expected to be, of at least 12 months.
Acquisitions of citizenship
The definition of citizenship is as stated in Article 9.3 of Regulation (EC) No 862/2007.
Loss of citizenship
The definition of citizenship is as stated in Article 9.3 of Regulation (EC) No 862/2007.
Legally induced abortions
A legally induced abortion is a termination of a pregnancy by abortion under the 1967 Act, as amended by the Human Fertilisation and Embryology Act 1990.
A legally induced abortion must be certified by two registered medical practitioners as justified under one or more of the following grounds:
— the continuance of the pregnancy would involve risk to the life of the pregnant woman greater than if the pregnancy were terminated (Abortion Act, 1967 as amended, section 1(1)(c));
— the termination is necessary to prevent grave permanent injury to the physical or mental health of the pregnant woman (section 1(1)(b));
— the pregnancy has not exceeded its twenty-fourth week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of the pregnant woman (section 1(1)(a));
— the pregnancy has not exceeded its twenty-fourth week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of any existing children of the family of the pregnant woman (section 1(1)(a));
— there is a substantial risk that if the child were born it would suffer from such physical or mental abnormalities as to be seriously handicapped (section 1(1)(d));
or, in an emergency, certified by the operating practitioner as immediately necessary:
— to save the life of the pregnant woman (section 1(4));
— to prevent grave permanent injury to the physical or mental health of the pregnant woman (section 1(4)).
Late foetal deaths
The Stillbirth (Definition) Act 1992 defines a stillbirth as:
“A child that has issued forth from its mother after the 24th week of pregnancy, and that did not at any time after being completely expelled from its mother breathe or show any signs of life”.
This definition has been in use since 1 October 1992. Prior to this, the Births and Deaths Registration Act 1953 defined a stillbirth as above, but at 28 or more weeks completed gestation.
Infant deaths
Deaths under 1 year of age.
Marriages
Annual marriage statistics for the UK and its constituent countries are based on the details collected when marriages are solemnised, the statistics are based on information recorded in the marriage register.
Figures for the UK, England and Wales, Scotland and Northern Ireland represent the number of marriages solemnised in a particular year in either a civil or a religious ceremony. Figures are derived from information collected as part of the marriage registration process.
Marriage figures are based on country of formation and not country of residence and relate only to marriages taking place in the constituent countries of the UK. They do not include marriages of UK residents taking place abroad, but do include non UK residents who marry within the UK. There is no legal requirement for UK residents who get married abroad to register their marriage with UK authorities.
Divorces
Annual divorce statistics for the UK and its constituent countries are based on information recorded when decrees are made absolute and decrees of nullity are given. Figures are derived from forms supplied by the courts. Figures for the UK, England and Wales, Scotland and Northern Ireland represent the number of marriages dissolved or annulled in a particular year (based on the date the decree absolute or decree of nullity was awarded). Figures are based on country of dissolution and not country of residence.
3.4.3 Differences in statistical concepts and definitions between the statistics transmitted to Eurostat and those disseminated in the National Statistics Institute's website
Population
None – the Usual Residence definition is used.
Population estimates refer to the usually resident population. This can mean that estimates of population do not necessarily coincide with the number of people to be found in an area at a particular time of the day or year.
For most people, defining where they usually live for the purposes of the census for example, is quite straightforward. For a minority of people the concept of usual residence is however more difficult to define, for example for students, members of the armed forces, prisoners and international migrants.
Specific rules are used for these groups:
— Higher education students and school children studying away from home are resident at their term-time address.
— Members of the armed forces are usually resident at the address where they spend most of their time.
— Prisoners are usually resident in the prison estate if they have a sentence of six months or more.
— International migrants are usually resident if they intend to stay in England and Wales for more then 12 months.
Live births
Live births are all births that occur and are then registered in the UK to usual residents. Births to UK residents which are registered outside the UK are excluded. Also Births that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (around 220 in 2017). Figures for England and Wales are based on births occurring in a calendar year. Figures for Scotland and Northern Ireland are based on births registered in a calendar year. The difference between providing wholly birth registration data for the UK in comparison to birth registration data for Scotland and Northern Ireland combined with birth occurrence data for England and Wales varied between 0.001 % and 0.43 % during the period 2006 to 2016 (between 10 and 3 400 births per year).
It should be noted that in England and Wales where a birth is registered too late to be included in the count for the year of occurrence, it will be included in the count for the following year. There are some births registered too late for this also but the numbers are low.
Deaths
Deaths are all deaths that occur and are then registered in the UK to usual residents. Deaths to UK residents which are registered outside the UK are excluded. Deaths that occur in one of the constituent countries of UK to a resident of another constituent country of UK are excluded although the numbers are small (less than 450 in 2017).
Figures are based on deaths registered in a calendar year.
Looking at England and Wales data for death registrations and death occurrences, the difference between the total death figures for a reference year varied between 0.01 % and 1.2 % during the period 2006 to 2016 (between 30 and 6 300 deaths per year). For Scotland, this varied between 0.0 % and 0.4 % during the period 2006 to 2016 (between 1 and 248 deaths per year).
It should be noted that death occurrence figures are extracted at a particular point in time in England and Wales, 10 months after the end of the calendar year. There will be more deaths registered after this point in time which will not be included within any death occurrence dataset. For example, there are currently between 1 700 and 3 800 deaths per year that are not included in England and Wales death occurrence datasets for the calendar years 2006 to 2016 (as of March 2018). Thus, death registration data provides a more complete time series of data. In Scotland and Northern Ireland, a death occurrence dataset is not routinely extracted so death occurrence figures will vary over time depending on when the data is extracted.
It should be noted that deaths registered in a reference year will include some deaths that occurred in previous year. For example, in the England and Wales, 5 % of deaths registered in 2017 were from previous years (around 27 800 deaths).
The deaths not included in the registration file are likely to be a mix of those deaths registered in early January for deaths in late December and those deaths referred to a coroner (or Procurators Fiscal in Scotland) ie those considered unexpected, accidental or suspicious.
The number of deaths to UK residents which are registered outside the UK is likely to be very small so has a negligible impact on statistics.
Immigrants
None.
Emigrants
None.
Acquisitions of citizenship
None.
Loss of citizenship
None.
Legally induced abortions
Not applicable.
Late foetal deaths
Stillbirths are all stillbirths that occur and are then registered in the UK to usual residents. Stillbirths to UK residents which are registered outside the UK are excluded
Figures for England and Wales are based on stillbirths occurring in a calendar year. Figures for Scotland and Northern Ireland are based on stillbirths registered in a calendar year. It should be noted that in England and Wales where a stillbirth is registered too late to be included in the count for the year of occurrence, it will be included in the count for the following year. The number of these is very small.
Infant deaths
Infant deaths are all infant deaths that occur and are then registered in the UK to usual residents. Infant deaths to UK residents which are registered outside the UK are excluded.
Figures are based on infant deaths registered in a calendar year. The infant deaths not included in the registration file are likely to be a mix of those infant deaths registered in early January for deaths in late December and those infant deaths referred to a coroner (or Procurators Fiscal in Scotland) ie those considered unexpected, accidental or suspicious.
It should be noted that infant deaths registered in a reference year will include some infant deaths that occurred in the previous year.
The number of infant deaths to UK residents which are registered outside the UK is likely to be very small so has a negligible impact on statistics.
Marriages
Marriages are all marriages that took place in the UK. Therefore the statistics do not include marriages to residents of UK that took place abroad and they do include marriages that took place in UK to non-residents.
Divorces
Divorces are all divorces that took place in UK following court orders. Therefore the statistics do not include divorces to couples usually resident in UK that took place abroad.
Number of persons.
Statistical population
Population
Usually resident population.
Live births
Not available.
Deaths
Not available.
Immigrants
The principal data source is the International Passenger Survey. The target statistical population is all travellers entering or leaving the UK through air and sea ports and the Channel Tunnel. The survey covers 95 % of travellers entering and leaving the UK.
Emigrants
The principal data source is the International Passenger Survey. The target statistical population is all travellers entering or leaving the UK through air and sea ports and the Channel Tunnel. The survey covers 95 % of travellers entering and leaving the UK.
Acquisitions of citizenship
Those that are acquiring British citizenship through application, based on a residence of 3 years for someone whose spouse or civil partner is British and 5 years for others.
Loss of citizenship
Under the British Nationality Act 1981 it is possible for British citizens who are over 18 years of age and of full capacity to apply to renounce their nationality, although renunciation will only be granted where that applicant already has or is about to acquire citizenship of another country. Further information on renunciation of British citizenship is available on the Home Office website: https://www.gov.uk/renounce-british-nationality.
Legally induced abortions
Not available.
Late foetal deaths
Not available.
Infant deaths
Not available.
Marriages
Not available.
Divorces
Not available.
Population, live births and deaths data are available at national and regional level of geographical detail.
The reference date for population data is the end of the reference period (midnight of 31 December). The reference period for vital and dual events data is the calendar year in which the events occurred. The reference period for migration flow data is the calendar year in which the migration occurred.
Overall accuracy and special cases (Inclusion/exclusion of asylum seekers and refugees, persons living on unauthorised or irregular basis, international students, persons who do not register/deregister,...)
Overall, the data quality for the total numbers of those granted and refused British citizenship is high. These data:
— are administrative counts of the Home Office’s casework processes, which are defined in UK legislation and are recorded under detailed categories on the Home Office’s administrative database;
— are scrutinised regularly as part of the performance monitoring of the Home Office;
— are regularly assessed as part of the Home Office’s Quality Assurance Framework;
— have not, in recent years, had to be altered significantly between initial provisional totals released in February each year and subsequent revised totals released in the following May and have not, in recent years, had to be revised at all when the annual data are subsequently checked 12 months later and the provisional status of the data is altered to final;
— do not require sampling processes for the compilation of the figures and hence have no associated sampling errors; and
— undergo a thorough reconciliation process including some data cleansing.
Loss of citizenship
Overall, the data quality for the total numbers of those granted and refused British citizenship is considered to be high. These data:
— are administrative counts of the Home Office’s casework processes, which are defined in UK legislation and are recorded under detailed categories on the Home Office’s administrative database;
— are scrutinised regularly as part of the performance monitoring of the Home Office;
— are regularly assessed as part of the Home Office’s Quality Assurance Framework;
— have not, in recent years, had to be altered significantly between initial provisional totals released in February each year and subsequent revised totals released in the following May and have not, in recent years, had to be revised at all when the annual data are subsequently checked 12 months later and the provisional status of the data is altered to final;
— do not require sampling processes for the compilation of the figures and hence have no associated sampling errors; and
— undergo a thorough reconciliation process including some data cleansing.
Legally induced abortions
Data quality and methods for abortions in England and Wales (Annex A)
Population Estimates are compiled by applying components of change to start-year population. Estimation of sex and age of migration data is made at local level. Estimation of place of usual residence is made at local level for armed forces based on 2011 Census results. Births and deaths data are coded, edited or imputed where necessary. Child deaths are linked with birth registrations using NHS number. For migration data, annual record editing is carried out where necessary. Some imputation of variables from best match donor within input stream in the quarter. Data processing and estimation occur within an internally developed computer system. Output reports are checked and include charts and logic to check balances produced. Totals in output spreadsheets are checked.
Birth statistics are based on information collected when a birth is registered.
Deaths
Mortality statistics are based on the information collected when a death is registered.
Immigrants
Main data sources are:
International Passenger Survey (ONS);
Asylum seeker approvals (Home Office);
Northern Ireland Health card data (NISRA);
Labour Force Survey (ONS - calibration only);
Emigrants
Main data sources are:
International Passenger Survey (ONS);
Asylum seeker approvals (Home Office);
Northern Ireland Health card data (NISRA);
Labour Force Survey (ONS – calibration only).
Acquisitions of citizenship
UK Border Agency administrative data drawn from the Case Information Database.
Loss of citizenship
UK Border Agency administrative data drawn from the Case Information Database.
Legally induced abortions
Abortion notifications.
Late foetal deaths
Stillbirth registrations.
Infant deaths
Infant death statistics are based on the information collected when an infant death is registered.
Marriages
Marriage statistics are based on the information collected when a marriage is registered.
Divorces
Divorce statistics are based on the information collected by the court service.
Surface in km2
Not Applicable.
Annual.
According to Art 4 (2) of the Commission Implementing Regulation (EU) No 205/2014, each year Member States shall provide the Commission (Eurostat) with data at national and regional level as described in Annex II and related standard reference metadata ( In the metadata structure definition defined for the Euro SDMX Metadata Structure) for the reference year within 12 months of the end of the reference year. According to Art 3 (2) of the Commission Regulation (EC) No 862/2007, Statistics on international migration, usually resident population and acquisition of citizenship shall be supplied to the Commission (Eurostat) within 12 months of the end of the reference year.
For population estimates, although there are small differences in methods between the constituent countries of the UK, the estimates are stated to be comparable for areas within the UK. This is documented at:
Birth statistics for England and Wales are based on the number of births occurring in the year, while Scotland and Northern Ireland statistics relate to the number of births registered in the year. In England and Wales where a birth is registered too late to be included in the count for the year of occurrence, it will be included in the count for the following year. The differences between reporting occurrences and registrations are minor and figures are broadly comparable.
Death statistics are based on the number of deaths registered in the year across the UK so are comparable.
For migration, estimates are comparable across the UK countries.
Comparability - over time
Population
Definitions have remained consistent since 2002, and estimates from 2002-2017 are all based on both the 2001 and the 2011 Census, thus allowing comparison over time. Plans for revisions to methodology, and the publication of a back-series covering 2012-2017, are available at:
A time series for the number of births is available back to 1887. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Deaths
A time series for the number of deaths is available back to 1887. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Immigrants
LTIM – Available from 1991 to 2018 (final data).
Data supplied to Eurostat for 2008 to 2018 are comparable.
More information on changes and comparability over time:
The first reference year for which data are available is 1968.
Late foetal deaths
A time series for the number of stillbirths is available back to 1961 (when registration of stillbirths first came into operation). The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table. The definition of stillbirth changed from 28 or more weeks completed gestation to after 24th week of pregnancy in October 1992.
Infant deaths
A time series for the number of infant deaths is available back to 1900. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Marriages
A time series for the number of marriages is available back to 1862. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
Divorces
A time series for the number of divorces is available back to 1971. The length of the time series available for more detailed breakdowns is dependent on which variables are contained in the table.
