5. UK population grew by 538,000 in the year to mid-2016

At the national level population change can be split into natural change (births minus deaths), net international migration (immigration minus emigration) and other change, which at the national level reflects changes due to armed forces personnel moving into or out of the UK.

Figure 2 shows that while natural change has increased, net international migration remains the largest component of population change. Overall, natural change accounted for 35.8% of the population change, net international migration for 62.4% and other changes 1.8%.

Figure 2: Population change for the UK, mid-1992 onwards Source: Office for National Statistics, National Records of Scotland, Northern Ireland Statistics and Research Agency Notes: Figures may not add exactly due to rounding. Other changes comprises changes to the size of armed forces stationed in the UK and other special population adjustments; and is combined with net international migration for the purposes of this graph. Download this chart Figure 2: Population change for the UK, mid-1992 onwards Image .csv .xls

Population change due to natural change, was 193,000 in mid-2016 (or 0.3% of the mid-2015 population), an increase of 21,000 on the previous year. It remains below the level of the peak seen between 2008 and 2014, but above the levels seen between 1992 and 2008. Figure 2 shows that natural change and overall change are slightly higher than in the year to mid-2015. Other changes increased, reflecting changes to armed forces personnel based in the UK; net international migration remained at a similar level to mid-2015.

Births and deaths

In the year to mid-2016, there were 781,000 births (an increase of 0.7% on the previous year) and 588,000 deaths (a decrease of 2.6%). Further analysis of fertility in the UK will be published by the Office for National Statistics (ONS) in July 2017.

The decrease in deaths is partly a result of the winter period 2015 to 2016 excess winter mortality significantly decreasing from the winter period 2014 to 2015. Further analysis from ONS has suggested that this was due mainly to the most prevalent strain of the flu virus impacting younger people rather than older people, who are more at risk.

Decreases in mortality over recent years have resulted in increasing life expectancies in the UK and a narrowing of the gap in life expectancies between men and women. This reflects a fall in the proportions of males who smoke or hold a higher-risk occupation. This is one reason why the ratio of males to females in the UK population has continued to increase. There are now 98 men for every 100 women, compared with 95 men per 100 women in mid-2005. The other main reason for the increase in this ratio is that net international migration results in more men residing in the UK as they tend to migrate to the UK more than women.

International migration

Net international migration in the year to mid-2016 was at a similar level to that seen in mid-2015, at 336,000 or 0.5% of the mid-2015 population. Compared with mid-2015, there were 13,000 more immigrants and 13,000 more emigrants. Analysis of the International Passenger Survey (IPS) data, that form the basis of these estimates, showed that these changes were not statistically significant. It showed that net migration remained around record levels, but it was stable compared with recent years; while immigration levels were among the highest estimates recorded.

In addition to the direct impact of migration on the size of the population, current and past international migration also has indirect effects on the size of the population as it changes the numbers of births and deaths in the UK. A fuller assessment of the indirect effect of migration on the size of the population would consider:

births to, and deaths of, people who had migrated to the UK

births to, and deaths of, people who emigrated from the UK (and who would have given birth, or died, in the UK had they not emigrated)

how to account for births to, and deaths of, UK-born people who had emigrated and subsequently returned to the UK

how to account for births to, and deaths of, UK-born people who had parents (or grandparents) who were themselves immigrants

Some additional information for England and Wales can be obtained in Parents’ Country of Birth 2015, this showed that in the calendar year 2015, of all births in England and Wales 27.5% were to mothers born outside of the UK. Background information on the UK population, its size, characteristics and the causes of population change is available in the Overview of the UK Population: March 2017.

Other changes

Other changes, comprising changes to the size of the armed forces stationed in the UK and other special population adjustments, tend to have small effects on the national population but can have a larger impact at a local level. In the year to mid-2016, the UK population increased by 9,500 due to other changes, compared with an increase of 5,800 in the year to mid-2015. This reflects trends such as the return of British Armed Forces based in Germany.