Today's 20-year-olds are twice as likely as their parents to reach the age of 100, a new analysis of Britain's rapidly ageing population reveals today.
A girl born this year has a one-in-three chance of becoming a centenarian, and a boy a one-in-four chance, the research by the Department for Work and Pensions discloses.
A girl born in 1931 had only a 5 per cent chance of reaching her century, with the figure dropping to jut 2.5 per cent for boys.
On current trends there will be half a million people aged 100 or over by the year 2066.
Steve Webb, the Pensions minister, warned that the huge advances in average lifespans meant people would need to save more for a retirement that could stretch into an 11th decade.
He said: "The dramatic speed at which life expectancy is changing means that we need to radically rethink our perceptions about our later lives. We simply can't look to our grandparents' experience of retirement as a model for our own."