但自1900年以来，这方面的收益不可谓不巨：1900年全世界寿命预期为32岁，如今为69岁（2050年的预测值是76岁 ） 。
Yet it is difficult to overstate the magnitude of the gain since 1900: in that year, life expectancy worldwide was 32 years, compared to 69 now (and a projection of 76 years in 2050).