Official figures show that a record number of people in the UK are retiring this year as the post-war “baby boom” generation draw their pensions.

The first detailed analysis of returns from the 2011 census shows that the overall number of people turning 65 has leapt by 30% in a single year.

With the population of the country steadily rising and life expectancy dramatically improving in recent decades, it means that there are more 65-year-olds in the UK than at any other point in history.

The sudden spike in numbers of people drawing their pensions for the first time reflects a surge in the birthrate after the end of the Second World War.

Those reaching 65 this year were born in 1947, part of the first wave of the so-called baby boom. It followed mass demobilisation of servicemen the previous year, which transformed family life in Britain after six years of war.

In addition, those approaching the end of working life anticipate, on average, an income of £17,000 per annum from their retirement arrangements, but the reality is that they will receive a sum closer to £10,000, leaving a worrying income gap.