The UK population increased more last year than at any time in almost half a century, because of a higher birthrate and increased life expectancy,There are 200,000 more women of child-bearing age than ten years ago, many of whom were born abroad and tend to have larger families than their British-born counterparts. As a result there were 134,000 more births last year than in 2001-02. Statisticians said another factor in the growing birthrate was the number of women born in the 1960s and 1970s who are tending to delay having children until an older age. At the other end of the age scale, there were 47,000 fewer deaths than eight years ago as longevity increases thanks to medical advances, notably in the treatment of heart disease. The numbers of people aged over 85 have more than doubled in a generation, from 600,000 in 1981 to 1.4 million today. In particular men are living longer: they now make up almost one-third of Britain’s over-85s, compared with 23 per cent in 1981. Migration accounted for 230,000 of the population increase as 574,000 immigrants came to the country last year while 344,000 people migrated overseas according to figures from the Office for National Statistics.  

Population: by gender and age, mid-2010

The estimated resident population of the UK was 62,262,000 in mid-2010, up by 470,000 on the previous year.

Children aged under 16 represented 19 per cent of the total population and those aged 65 and over represented 17 per cent of the total population. In mid-2010 the average age of the population was 39.7 years, up from 37.9 in 2001.

The diagram above is a representation of the age and sex structure of the population, known as a population pyramid. Each bar represents a particular single year of age and the length shows the population of that age. The structure of the pyramid is determined by births, deaths and international migration.

Up to the age of around 70, the number of males and females are fairly equal. At older ages, towards the top of the pyramid, females outnumber males. This is shown by longer bars on the female side of the pyramid. The ratio of females to males increases progressively from 1.1 at age 70, to 2.1 by the age of 89. This reflects the higher life expectancy of women at older ages and higher male mortality during the Second World War. The population pyramid stops at age 89, causing the top of the pyramid to be flat.

Further down the pyramid, people aged between 16 and 64 represent 65 per cent of the total mid-2010 population. The bulge in the pyramid for people in their mid 40s is due to the ‘baby boom’ years of the 1960s and early 1970s.

A sharp narrowing of the pyramid for people in their early 30s reflects the low fertility in the late 1970s. A further narrowing of the pyramid appears between the ages of 6 and 12 reflecting the low fertility rates in the early 2000s. The broadening of the base of the pyramid is due to increasing numbers of births from mid-2002 onwards, reaching just under 797,000 in the year to mid-2010.

Notes:
Estimates of the Very Elderly (those aged 90 and above) for mid-2010 are planned for publication on 29 September 2011.

Average age – the median age has been used here which means half the population are older and half the population are younger.