Forecasts of maximum age

Demographic projections of maximum age to the year 2100 have produced mixed results. Mortality plateau models used in some studies have tended to predict relatively high ages over 130 years by the end of the century. We use the latest validation and count of supercentenarians in the G12 countries to test models of ageing beyond 100 years and conclude that a linearly increasing hazard model is a better fit. Plateau models starting in the age range 105 to 110 years are strongly excluded. Baseline forecasts of expected maximum age can be calculated using global projections of centenarian numbers with working assumptions that no new medical advances or global disasters would change the outlook. The linear model then leads to more modest forecasts of maximum lifespan of around 124 years by 2100. Our models are statistically in tension with the claim that Jeanne Calment lived to the outlier age of 122 years in 1997. Her claim is examined in the light of new evidence including signature samples from around 1933 when we believe an identity switch with her daughter took place.