Each year, the Office for National Statistics (ONS) publishes ‘mid-year estimates’ of populations at national and local authority levels. These are based on Census data, updated to allow for subsequent birth rates, death rates and estimated migration patterns using sources such as regional birth and mortality records, the International Passenger Survey (IPS) and National Asylum Support Service for international migration, Labour Force Survey, Higher Education Statistics Agency (HESA) and the GP Patient Register database (PRDB, for internal migration).
Key Facts for Somerset
In the year to 30th June 2016, Somerset’s population is estimated to have increased by 4,057 to 549,447.
Amongst the 65-74 age group, the annual rate of growth was an estimated 3.5%, five times the average rate. This partly reflects the attraction of Somerset as a retirement destination, and also the post-war baby-boom generation reaching retirement age.
All Somerset districts, with the exception of West Somerset, experienced an increase in population.
West Somerset has the highest number of total moves in and out per head of population of any of the five Somerset districts (132 per 1,000).
There were more deaths than births in 2015/16, although in Sedgemoor the reverse was true.
In 1991, the largest five-year age group was 40-44. In 2016, it was the 50-54 age group but the post-WW2 ‘baby-boom’ 65-69 age group is only slightly smaller.
87% of the overall growth in Somerset is explained by internal migration. In the year to June 2016, 3,896 more people moved into Somerset from elsewhere in the UK than moved out.
Somerset continues to see a net ‘inflow’ across most age groups, but with a key exception being the 18-20 age group. Amongst 18-20 year-olds, 2,100 more moved away than moved in, most commonly to the university cities of Cardiff, Plymouth, Bath and Bristol.
The annual net increase in international migrants was 286. This was well below the levels seen in the period a decade ago following the A8 Eastern European nations’ accession to the EU.
Somerset's population is projected to continue rising by at least 3,000 a year for the next two decades or so, reaching 600,000 by 2030.
The number of people aged 75 or older is projected to double by 2039.
The 2016 mid-year estimates were published in June 2017 and indicate that the population of Somerset has risen by 4,057 to 549,447. The total is broken down by age group and district in the table below.
The charts below illustrate how the populations of Somerset and the five Districts have changed markedly in the past 25 years, not only in size, but also in their age and gender profile. On the charts, you can see the actual numbers by hovering the cursor over the appropriate line or bar.
What if Somerset Districts were sized based on their population? The map below shows what the County might look like if the size of the Districts was proportional to their population.
Components of population change
Overall in Somerset, for the second successive year there was a negative ‘natural’ change in population, with deaths exceeding births (see table below). Sedgemoor was the exception.
Components of Population Change in Somerset, year ending June 2016
Births - Deaths
As usual, the majority (almost 90%) of the estimated year-on-year increase in Somerset’s population is due to internal migration (i.e. migration from other parts of the UK). There was a net ‘inflow’ to Somerset of 3,896 people in the year to June 2016, the highest figure since 2004.
By comparison, net international inflow (that is, people from outside the UK) fell to 286 people, the lowest number since at least 2002 (from which comparable data is available).
Somerset has a population density of 159 people per square kilometre (sq km). Each of the five districts in the county has a population density below that of the UK average (271 per sq. km). West Somerset's population density of 47 per sq km is the fifth lowest of any local authority in England.
Local Area Population Estimates
In October 2016, the ONS published population estimates for June 2015 by age group at smaller geographies, such as District electoral Ward and Lower level Super Output Area (LSOA). Headlines include:-
The mean population of the 138 wards in Somerset is just under 4,000.
Population sizes range from 9,024 in North Petherton ward to 1,095 in West Quantock ward.
Since the 2011 Census, 96 wards are estimated to have gained population, while 42 are estimated to have seen a decrease.
Since 2011, the largest estimated increases have been in North Petherton ward (1,869 residents, a rise of 26%) and Kings Isle ward (1,065, 24%).
Since 2011, the largest estimated falls have occurred in Minehead Central ward (234, 5%) and Taunton Eastgate ward (191, 4%).
Based on Lower level Super Output Areas (LSOAs) in 2015, the area with the highest population density is Taunton Rowbarton South (9,705 per sq km), and the lowest is Exford (just 7 per sq km).
For detailed figures for Wards and LSOAs in Somerset, please click here.
For data on all geographies across England and Wales, please go to the ONS website.
In May 2016, the ONS released new population estimates projected to the year 2039 by single year of age by local authority, based on the 2014 mid-year estimates. The Somerset population is projected to rise by around 82,000 (15%) over the twenty-five year period, to 623,600 (see chart below).
Projected growth amongst the 65+ age group is even greater, at around 61%, and the number of people aged 75 or more is projected to double over the period, to 116,000.
The under-16 population is projected to increase by 9% by 2039, with the great majority of this increase in the next ten years. The ‘working age’ population is projected to witness a 2% decline over the next twenty-five years, with most of the fall coming beyond 2024.
Between 2014 and 2039, Sedgemoor and Taunton Deane are projected to experience the highest growths in percentage terms, 22% and 17%, respectively. The projected trend totals for selected years are shown below.
The 'population pyramid' below highlights the ageing profile of Somerset residents.
In 1961 (see the light coloured lines), the post-war baby boom led to a 'spike' in teenagers.
In 2013 (bars), the most populous age groups are those in their 40s, 50s and 60s
By 2033 (darker lines), there is projected to be a bulge in the 70-79 age groups, with almost as many in their 80s as in their 20s
Comparison of the population in 2013, and local projections, show how most of Somerset, including almost all rural areas, is likely to have at least 25% of the population over 65 by 2033 (see maps below)
Proportion of population aged 65 and over, 2013
Proportion of population aged 65 and over, 2033
Each district can expect to see a significant increase in the numbers of people over 65 by 2037. The chart below show the projected increase of over 65s between 2013 and 2037, in most cases it is over 50%.
Note that these are trend-based projections, which means assumptions for future levels of births, deaths and migration are based on observed levels mainly over the previous five years. They show what the population will be if recent trends continue and don't take into account any policy changes that have not yet occurred (e.g Hinkley Point construction), nor those that have not yet had an impact on observed trends.
Note, too, that as the period since the latest Census increases, so will the likely inaccuracy of population estimates. Furthermore migration data, particularly international, are relatively unreliable at local levels because IPS samples are very small at small geography levels, requiring combining of areas and time periods.
For the latest information about birth rates in Somerset, population projections for children and young people and school roll forecasts, please go to the pages below.
Looking ahead to 2021 and beyond, the ONS has established a Census Transformation Programme. Its aim is to make the best use of all available data in England and Wales to enhance the provision of population statistics. It will:-
provide an online census in 2021,
seek to increase the use of administrative data to enhance population statistics,
form plans for the provision of population statistics after 2021.
For example, the ONS have carried out extensive research into the use of administrative data (such as those held by the DWP, NHS Patient Registers and School Census) to generate unofficial estimates of local population sizes.
In November 2016, this methodology provided retrospective estimates for Somerset which are higher than the 2011 Census and 2015 mid-year estimates. More work is being done to understand the differences. However, there is evidence that higher estimates are often found in areas, such as Somerset, with relatively high numbers of seasonal workers, residential schools and people contacting administrative services (eg health and social care).