For the world in 1990, the project estimated that 56.8 of the 64.5 years of life that an average person could be expected to live were years of healthy life. And at least in developed countries, where estimates are available for 2010 as well, we know that out of the 4.7 years of additional expected life we gained in those two decades, 3.8 were healthy years.14 Numbers like these show that people today live far more years in the pink of health than their ancestors lived altogether, healthy and infirm years combined.
