Population estimates for the UK, England and Wales, Scotland and Northern Ireland: mid-2013

• This release marks the first time that all small area population estimates have been published together in a single release. It includes estimates for lower and middle layer Super Output Areas (LSOAs and MSOAs), Westminster parliamentary constituencies, electoral wards and National Parks in England and Wales and clinical commissioning groups (CCGs) in England

• In mid-2013 there were 34,753 LSOAs in England and Wales with a mean population of 1,640 and 7,201 MSOAs with a mean population of 7,910. The LSOA with the highest median age in mid-2013 was Eastbourne 012B at 70.8 years

• There are 211 CCGs in England which had a mean population size of 255,300 in mid-2013. The CCG with the largest proportion of the population aged 75 and over was NHS Eastbourne, Hailsham and Seaford at 13.3%

• The 573 Westminster Parliamentary Constituencies in England and Wales had a mean population of 99,400 in mid-2013. On average English constituencies tend to have larger populations than Welsh constituencies (means of 101,100 and 77,100 respectively)

• In mid-2013 electoral wards in England and Wales had a mean population of 6,690 although population sizes ranged from 150 in St. Martin’s ward in the Isles of Scilly to 39,690 in Central ward in Sheffield

• The population of National Parks have an older age structure than England and Wales as a whole. More than 30% of the population of Exmoor and The Broads are aged 65 years or over

• Small area population estimates are of particular use to central and local government for planning and monitoring services and for the calculation of a range of rates and indicators

This bulletin presents the 2013 mid-year population estimates for small areas within England and Wales. It brings together in one place a range of population estimates products that were previously published separately.

The products included in this release are:

• Population estimates for lower and middle layer Super Output Areas (LSOAs and MSOAs) in England and Wales – these products are classified as National Statistics

• Population estimates for electoral wards, Westminster parliamentary constituencies and National Parks in England and Wales – these products are classified as experimental statistics

• Population estimates for health geographies in England (Clinical Commissioning Groups, NHS Area Teams and NHS Commissioning Regions) – these products are also classified as experimental statistics

These estimates are consistent with the results of the 2011 Census and are provided for the latest official geographic boundaries in place at the reference date

Small area population estimates are used by both central government departments and local authorities for a range of purposes including planning and monitoring of services and as denominators for the calculation of various rates and indicators. Population estimates for LSOAs and MSOAs are often used for research and analysis as, unlike other small area geographies such as electoral wards, they are specifically designed for statistical purposes. Electoral ward population estimates are of particular interest to local government organisations; parliamentary constituency estimates are of importance to parliamentary organisations, researchers and MPs; population estimates for health geographies are widely used within the health sector; and information on National Parks is valuable to both local government and the various National Park authorities.

Mid-year population estimates for 2013 for England and Wales, regions within England, and local authorities within England and Wales, were published on 26 June 2014. The estimates refer to the usually resident population as at 30 June of the reference year and are published annually. In mid-2013 the population of England and Wales was 56,948,200, an increase of 0.7% since mid-2012 and 7.7% over the 10 years since mid-2003.

Small Area Population Estimates

There are two broad types of small area population estimates, both of which are included in this release.

The main products are the estimates for Super Output Areas (SOAs), which are based on the 2011 Census and rolled forward annually using a ratio change methodology. This approach uses the change in the population recorded in administrative sources as an indicator of the change in the true population. These products hold National Statistics status.

The remainder of small area population estimates products relate to a range of different geographic areas and are derived directly from the SOA figures. Firstly, estimates for lower layer Super Output Areas (LSOAs) are broken down to output area (OA) level using an apportionment approach. These OA estimates are then aggregated to produce estimates for electoral wards and Westminster parliamentary constituencies on a best-fit basis. Estimates for health geographies are aggregated directly from LSOAs and estimates for National Parks are also calculated from the OA level data. These products hold Experimental Statistics status.

More information on the types of area for which small area population estimates are produced is given in the short story accompanying this release.

The mid-2013 small area population estimates covered by this bulletin are fully consistent with population estimates for higher levels of geography including local authorities, regions and the national total for England and Wales. A full description of the methods used to calculate all small area population estimates is available in the methodology guide published on the ONS website.

Small area population estimates are used by both central government departments and local authorities for a range of purposes including planning and monitoring of services and as denominators for the calculation of various rates and indicators. For further information on the quality and use of these statistics, please see the Quality and Methodology Information for small area population estimates.

Super Output Areas (SOAs) are statistical geographies designed to improve the reporting of small area statistics. They are built from groups of census output areas, are of a consistent size and are not subject to boundary changes between censuses. Where possible they are formed from groups of socially similar households and align with local features such as roads and railway lines. The comparability and stability of the geography is a key benefit to users of statistics which cannot be provided by other small area administrative geographies such as wards or parishes.

At mid-2013, the mean population of lower layer Super Output Areas (LSOAs) in England and Wales was 1,640, with population sizes ranging from 820 in South Cambridgeshire 004A to 8,250 in Oxford 008A. This area of South Cambridgeshire covers an area north-east of Cambridge including the former army barracks at Waterbeach, while Oxford 008A includes many colleges belonging to Oxford University.

The mean population of middle layer Super Output Areas (MSOAs) was 7,910 in mid-2013. Excluding the Isles of Scilly, the smallest MSOA (Forest of Dean 006) had a population of 4,950 whilst the MSOA with the largest population at mid-2013 was Richmondshire 004 with approximately 16,760 usual residents. This area has a high population of armed forces including those stationed at Catterick Garrison.

As shown in figure 1, annual population change was less than 1% in approximately 43% of LSOAs and less than 5% in about 95% of LSOAs. Lower rates of change were seen in the larger MSOA areas.

Age distribution

The median age of the population of England and Wales in mid-2013 was 39.8.

The median age for LSOAs within England and Wales varies widely between different areas. In mid-2013 the highest median age was 70.8 in Eastbourne 012B. Seven of the top 10 LSOAs with the highest median ages, as shown in table 1, are located close to the south coast of England in areas that are known for their large populations of people of retirement age. The exceptions are South Lakeland 013D located next to Morecambe Bay in Cumbria; Wealden 018A which is a rural area located close to the South Downs National Park; and King’s Lynn and West Norfolk 017D which is located in the town of Downham Market.

The lowest median age in an LSOA was 17.2 in Salford 016E, an area to the north-east of central Salford. 7 of the top 10 areas contain boarding schools, whilst one includes part of Newcastle University.

Population density

LSOAs are designed to have similar levels of population. Population density, that is the number of people living per square kilometre, can be used to highlight how different LSOAs are in terms of the geographic size of population settlements they include.

In mid-2013, the population density of England and Wales was 377 persons per square kilometre. Approximately 85% of LSOAs had a population density higher than that of England and Wales as a whole. Population density was less than 1,000 persons per square kilometre in approximately 23% of LSOAs, while approximately 8% had a population density of 10,000 or more persons per square kilometre.

The 10 LSOAs with the highest levels of population density are all in London. The LSOA with the highest population density in mid-2013 was Tower Hamlets 032D. This is an area where approximately 2,700 people live in 0.03 square kilometres, resulting in a density of 80,300 persons per square kilometre. It is located on the western side of Millwall Inner Dock on the Isle of Dogs. The most densely population LSOA outside of London was Sheffield 074E (an area of Sheffield city centre) at 33,900 persons per square kilometre (ranked 26th overall).

9 of the 10 least densely populated LSOAs in mid-2013 are in either North East England or Wales, with the top four all being in Northumberland. The least densely populated LSOA in England and Wales is Northumberland 019C with a population density of approximately 2.6 persons per square kilometre in mid-2013. This LSOA includes approximately 670 square kilometres of the area surrounding Kielder Water and some central parts of the Northumberland National Park. Seven of the top 10 areas shown in table 4 are either wholly or partly contained within a National Park area.

Notes for Super Output Area population estimates

1. Population density is calculated as the population estimate of each SOA divided by its land area in square kilometres. Land area is measured to the mean high water mark for coastal areas and excludes areas of inland water. This is the Eurostat recommended method for compiling population density figures. Land area is obtained from the Standard Area Measurements published on the ONS Geography Portal

Clinical commissioning groups (CCGs) are responsible for deciding how NHS funds are spent in their local area. They were introduced, for England only, by the Health and Social Care Act 2012 as part of a new structure for NHS organisation which came into force on 1 April 2013. The 211 CCGs are organised into 25 NHS Area Teams, which in turn are grouped into four NHS Commissioning Regions. The data tables included in this release also provide population estimates for these higher health geography areas.

CCGs replaced the former health geography areas known as Primary Care Organisations (PCOs). Following a formal consultation, ONS has discontinued the production of population estimates for PCOs.

The mid-2013 CCG population estimates, referred to in this bulletin, are direct aggregations of mid-2013 lower layer Super Output Area (LSOA) estimates. They are consistent with population estimates for higher levels of geography including local authorities and the national total for England.

At mid-2013, the mean population of CCGs was 255,300 with population sizes ranging from 64,200 in NHS Corby to 874,300 in NHS North, East, West Devon.

Annual population change

Table 5 shows the 10 CCGs with the largest percentage increases in population, seven of which are in London. The CCG with largest percentage increase in population between mid-2012 and mid-2013 was NHS Tower Hamlets at 3.8%.

In total, 14 CCGs (6.6%) had a population decrease between mid-2012 and mid-2013, with the greatest percentage decrease in population being 0.6% in NHS Hammersmith and Fulham (which covers the same area as Hammersmith and Fulham local authority). The remaining CCGs all had decreases of less than 0.5% and, with the exception of NHS Isle of Wight, were all in the North of England commissioning region.

Age distribution

The age distribution of the resident population in a CCG is likely to impact on both the overall level of demand for health services, and the type of health services required. Areas with a large percentage of older people in their population are likely to have different demands on health services than those with a predominantly younger population.

In mid-2013, 7.9% of the population of England were aged 75 or over. By comparison, over 13% of the population in NHS Eastbourne, Hailsham and Seaford were aged 75 or over. All of the CCGs shown in table 6 are coastal areas.

The percentage of the population who are children may also impact on requirements for health service provision. In mid-2013, 19.0% of the population of England were aged 0 to 15. By comparison, nearly 28% of the population in NHS Bradford City were aged 0 to 15, as shown in table 7. The CCGs with the largest proportions of children are in city areas.

Westminster Parliamentary Constituencies are the areas used to elect Members of Parliament (MPs) to the House of Commons, the primary legislative chamber of the UK. The current boundaries were introduced for the May 2010 General Election and include 533 constituencies in England and 40 in Wales.

At mid-2013, the mean population of parliamentary constituencies in England and Wales was 99,400 with population sizes ranging from 56,700 in Aberconwy to 163,400 in West Ham. On average, English constituencies have larger populations than Welsh constituencies with mean populations of 101,100 and 77,100 respectively.

Annual population change

Population change at parliamentary constituency level between mid-2012 and mid-2013 varies across the country, as shown in map 1 below.

Map 1: Percentage change in parliamentary constituency population estimates, mid-2012 to mid-2013

Parliamentary constituencies with the greatest increases in population over the one-year period tend to be concentrated in London, the South East of England, and city areas in the midlands and north of England. The area with the greatest increase was Poplar and Limehouse constituency in London at 3.9%, while the area with the greatest increase outside of London was Newcastle upon Tyne Central at 2.9%.

Population decreases at parliamentary constituency level occur across the country but are generally concentrated in the north of England and Wales. However, the two constituencies with the largest decrease (0.8%) were both in London (Hammersmith and Kensington).

Parliamentary constituencies are classified into two broad types of area: borough constituencies, which are defined as predominantly urban areas; and county constituencies, which are partly or mostly rural areas. The designation of a constituency as either borough or county is made by the relevant Boundary Commission. Overall, 55% of constituencies are classified as county constituencies and 45% are classified as borough constituencies.

As shown in figure 2, borough constituencies account for the majority of areas where the population has increased by more than 1% in the year to mid-2013. The mean percentage population change for county constituencies is 0.5% compared to 0.8% for borough constituencies.

Voting age

In England and Wales in mid-2013 there were 44,811,600 persons aged 18 and over, making up 78.7% of the total usual resident population. In mid-2013, at parliamentary constituency level, the percentage of the population aged 18 and over varied from 66.2% in Birmingham, Hodge Hill to 86.6% in Cities of London and Westminster.

The population of voting age in a parliamentary constituency is not the same as the population who are entitled to vote as it includes people who are not eligible to vote. For example, European Union citizens (excluding British citizens; and Irish, Cypriot and Maltese citizens who are qualifying Commonwealth citizens) are not entitled to vote in Westminster parliamentary elections but are included in the population estimates if they are resident in the UK for 12 months or more.

Electoral statistics, providing counts of the number of persons registered to vote in each parliamentary constituency, are available on the ONS website.

Electoral wards are a key building block of UK administrative geography. They are the spatial units used to elect local government councillors in metropolitan and non-metropolitan districts, unitary authorities and London boroughs in England; and unitary authorities in Wales. In some unitary authorities in England they are legally termed as ‘electoral divisions’, however they are frequently referred to as wards and are referenced as such throughout this article. The five parishes of the Isles of Scilly are also treated as electoral wards for statistical purposes.

Electoral wards are subject to annual updates and boundary changes. Mid-2013 population estimates are therefore provided for the 8,515 electoral wards in England and Wales as at 31 December 2013, excluding the 18 wards which do not meet the minimum population requirements for data confidentiality (40 resident households and 100 resident people in the 2011 Census).

At mid-2013, the mean population of wards in England and Wales was 6,690. However, population sizes vary widely across the country ranging from 150 in St. Martin’s ward in the Isles of Scilly to 39,690 in Central ward in Sheffield. On average, wards in England have larger populations than those in Wales with mean populations of 7,030 and 3,620 respectively.

Annual population change

Figure 3 presents the distribution of the percentage change in electoral ward populations, from mid-2012 to mid-2013.

The large majority of wards (86%) had an annual population change of less than ±2%, with around 5,200 (61%) increasing or decreasing by less than 1% in the year to mid-2013. There were 142 wards which had an annual population change of more than ±5% over the same period.

In particular, the wards with the highest percentage increases in population between mid-2012 and mid-2013 tend to be areas which include new housing developments, or areas with large populations of students or armed forces.

National Parks are designated areas of protected countryside aimed at conserving the natural beauty, wildlife and cultural heritage of the area. Each National Park has a National Park Authority (NPA) responsible for conservation, planning, recreation management and fostering the social and economic wellbeing of local communities.

The Broads does not have a National Park designation but is included in this set of statistics as it is part of the National Parks family. The Broads has similar responsibilities to NPAs but with additional powers relating to navigation. In total there are 13 National Parks in England and Wales (including the Broads).

Map 2: National Parks in England and Wales

Source: Office for National Statistics

In mid-2013 the mean population size of National Parks in England and Wales was approximately 31,000. However, National Park population totals vary greatly, as shown in figure 4. The most populous National Park, the South Downs, has 113,800 people compared to only 2,000 in Northumberland National Park.

Age distribution

National Parks have an older age structure than the wider population of England and Wales. In mid-2013 the median age of National Parks in England and Wales varied from 47.3 in the South Downs to 55.0 in Exmoor. In contrast, the median age for England and Wales as a whole was 39.8.

Figure 5 shows the percentage of the population of each National Park aged 65 and over, a figure which provides a reasonable proxy for the size of the population who are of retirement age. It shows that all 13 National Parks have a larger population aged 65 and over than England and Wales as a whole. In mid-2013, 17% of the population of England and Wales was aged 65 and over, compared to 21% in Northumberland National Park and over 30% in Exmoor and The Broads.

Population estimates are produced for similar small areas in both Scotland and Northern Ireland, however they are not produced using the same methodology as for small area population estimates in England and Wales.

National Records of Scotland (NRS) produce population estimates for Scottish data zones, which are slightly smaller areas than LSOAs designed to contain approximately 500 to 1,000 household residents. NRS use a cohort component based method to produce estimates for data zones, further information on this methodology and the latest estimates (for mid-2013) are available from their website.

The Scottish data zones are used to produce population estimates for a range of other geographies including Westminster parliamentary constituencies in Scotland, Scottish parliamentary constituencies, and Nomenclature of Units for Territorial Statistics (the statistical geography used by the European Union). These figures are available from the Special Area Population Estimates section of the NRS website.

The Northern Ireland Statistics and Research Agency (NISRA) publish population estimates for Super Output Areas in Northern Ireland. These are of similar size to English and Welsh LSOAs with populations of approximately 1,300 to 2,800 with a target size of 2,000. NISRA use a mixed methodology based on both cohort component and ratio change approaches. Further information and the latest estimates published for mid-2013 are available from the NISRA website. Population estimates for wards and Neighbourhood Renewal areas in Northern Ireland are also available.

A paper, Small Area Population Estimates across the UK which provides a broad description of the different methodologies used to produce small area population estimates in each constituent country of the UK, is also available on the NISRA website.