Projections of life expectancy in 35 industrialised countries: projections with a Bayesian model ensemble

Background: Projections of future mortality and life expectancy are needed to plan for health and social services and pensions. Our aim was to forecast national age-specific mortality and life expectancy using an approach that takes into account the uncertainty related to the choice of forecasting model. Methods: We developed an ensemble of 21 forecasting models, all of which probabilistically contributed towards the final projections. We applied this approach to forecast age-specific mortality to 2030 in 35 industrialised countries with high-quality vital statistics data. We used age-specific death rates to calculate life expectancy at birth and at age 65 years, and probability of dying before 70 years of age, with life-table models. Results: Life expectancy is projected to increase in all 35 countries with a probability of at least 65% for women and 85% for men. There is a 90% probability that life expectancy at birth among South Korean women in 2030 will be higher than 86.7 years, the same as the highest life expectancy in 2012, and a 57% probability that it will be higher than 90 years. Female life expectancy in South Korea is followed by those in France, Spain and Japan. For men, there is > 95% probability that life expectancy in South Korea, Australia and Switzerland will surpass 80 years in 2030, and 27% that it will surpass 85 years. The USA, Japan, Sweden, Greece, Macedonia and Serbia have some of the lowest projected life expectancy gains for both men and women. The female life expectancy advantage over men is likely to shrink by 2030 in every country except Mexico, where female life expectancy is predicted to increase more than male life expectancy, and in Chile, France, Greece, and Romania where the two sexes will see similar gains. More than half of the projected gains in life expectancy at birth in women will be due to enhanced longevity above 65 years of age. Conclusions: There is more than a 50% probability that by 2030, national female life expectancy will break the 90-year barrier, a level that was deemed unattainable by some at the turn of the 21st century. Our projections demonstrate the continued success of extending longevity, and the need for careful planning for health and social services and pensions. Funding: UK MR