Poverty, health and longevity
Poverty levels are always linked to early deaths due to specific causes. In poor and middle-low income countries, four out of ten deaths correspond to children under 15 years of age and only two out of ten to over 70 years old. In countries with high and medium-high incomes, only one in every hundred deaths occurs in children under 15 years of age and seven out of every ten correspond to those over 70.
These figures condition the estimate of the Life Expectancy at Birth, which is an excellent indicator of global health and well-being. Life expectancy at birth of Spanish women was 37 years in 1900 and 85.5 in 2015. On that date, Sierra Leone (50.1) and Nigeria (54.5) presented the lowest values ??in the world, compared to maximum of Japan (83.7) and Spain, (82.8), (joint EV for both sexes).
The demographic records are very modern, but some indicators can be estimated, such as life expectancy from parochial death records, or from the information provided by tombstones.