Mitra S
Demography. 1978 Nov;15(4):621-3.
When the force of mortality is reduced by a constant fraction delta at every age, the relative increase in life expectancy e(0) can be measured by deltaH, where H is determined by the l(a) values of the life table. Although H is not easily reducible in terms of the well-known life table parameters, it has been shown that it can be approximately estimated by 2 - e(0)/a in which a is the average age of the stationary population. It has been found that, for a given value of delta, the relative gain in life expectancy is less appreciable in countries with larger values of e(0).
当每个年龄段的死亡率降低一个固定比例δ时，预期寿命e(0)的相对增加量可以用δH来衡量，其中H由生命表的l(a)值决定。尽管根据著名的生命表参数，H不容易简化，但已经表明它可以用2 - e(0)/a来近似估计，其中a是稳定人口的平均年龄。已经发现，对于给定的δ值，在预期寿命e(0)值较大的国家，预期寿命的相对增加不太明显。
