Key Trends in Longevity to 2025 and BeyondContinuing Mortality Improvements at Older Ages Mortality rates in the UK are declining at all ages and for both sexes, just as they are in rest of the developed world. With every year that passes, there is an increase in the proportion of successive birth cohorts that reaches retirement age 1 , and an increase in the likelihood of surviving to enjoy that retirement for several years 2 . Declining mortality at older ages is one of the main drivers of the growth in the relative size of the older population. By 2025 one in five people in the UK population will be aged 65 years or more. By 2050 it will be almost one in four.Since most deaths now occur in later life, it is the continuing improvement in late life mortality that is contributing most to increasing life expectancy at birth. Over the last 20 years in the UK, male life expectancy at birth has increased by 5.6 years, i.e. at an average rate of more than three months per year, with most of the gain accruing to men past the age of retirement. Four of those additional life years have been added to life expectancy at the age of 65. Death rates in older men have not only fallen sharply in this time-by almost one half in the 60-69 age group and one third in the Population Ageing (2008) 1:225-240 1 Premature mortality among males (<65) declined from 24.4% in 1984-6 to 16% in 2004-6; and among females from 14.9% to 11.1% over the same period. 2 Over the last 20 years the chances of a 65 year-old women reaching the age of 80 have improved from 61% to 71%. Although the odds for a 65 year old man are not so good, they are still better than evens (59%), and much better than they were 20 years ago (41%).