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Article: Life Expectancy and Life Tables
- Article from:
- Encyclopedia of Public Health
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LIFE EXPECTANCY AND LIFE TABLES
A life table converts a set of age-specific mortality rates into a survival curve, from which summary statistics, such as life expectancy, can be derived. The procedure was developed first for humans, primarily for the purpose of calculating premiums for life insurance and annuities. Later the same approach was used to study the survival of patients, other living species, and inanimate objects.
Crude life tables were produced by the Roman Aemilius Macer in Rome in 225 c.e., and by John Graunt and William Petty in the seventeenth century. The astronomer Edmund Halley, in 1693, was the first to employ correct mathematical methods to calculate a life table, ...