Population aging is an international concern, in part because of consequences of coming age-structure changes, e.g., growth in the number of elderly, decline in the number of youth, and accompanying economic and social costs (1–4). These expectations are based on conventional measures of aging that link expected phenotypes to fixed chronological ages. But as life expectancies increase and people remain healthy longer, measures based solely on fixed chronological ages can be misleading. Recently, we published aging forecasts for all countries based on new measures that account for changes in longevity (5–8). Here, we add new forecasts based on disability status. Both types of forecasts exhibit a slower pace of aging compared with the conventional ones.

Low birthrates in Europe have begun to generate negative population momentum, a new force for population shrinkage over the coming decades. Birthrates are low partly because of the current trend in Europe toward bearing children at later and later ages. A continuation of this trend could substantially exacerbate future aging of the population and contribute to a future decline in population size. Social policies and labor laws aimed at halting further increases in the mean age of childbearing are proposed in this Policy Forum.