Similarly, vaccination has been shown to lead to wage gains across populations, while improvements in child survival rates are associated with lower fertility rates. And, in terms of the wider gains, one study found that a five-year improvement in life expectancy can translate into a 0.5-percentage-point increase in annual per capita income growth.
类似地，有证据表明疫苗可以引起整个人口的工资增加，而儿童存活率与更低的生育率有关。此外，从更广的范围看，有一项研究发现，人均收入增长提高0.5个百分点可以让期望寿命增加5年。