Like many of his literate and well-educated contemporaries, John Graunt (1620–1674), a London merchant and haberdasher, was an amateur scientist. He was a member of the small community of scholars who were early Fellows of the Royal Society, which was founded by King Charles II just as Graunt reached his years of greatest creativity. Graunt was interested in the fluctuations in epidemics, especially the plague, and how these caused the numbers of deaths, and the age at death, to vary from one year to another. For over one hundred years English parishes had kept records of baptisms and deaths, and what was then under-stood about causes of death was derived from these "bills of mortality," which Graunt collected and analyzed. He found differences in death rates between the sexes, between the city and the outlying rural and more remote regions, and he analyzed the ebb and flow of the epidemics of plague. He published his work in Natural and Political Observations … Made upon the Bills of Mortality (1662), now regarded as a seminal work in vital statistics.
Graunt influenced, and was influenced by, Sir William Petty (1623–1687), author of Political Arithmetic and other works that analyzed available facts in a number of areas, including life expectancy and earning capacity, emphasizing their economic and fiscal implications. There has long been debate about which of these two men should be credited with founding the statistical study of births and deaths. Both deserve to be remembered, but of the two, John Graunt, though he had less formal education, was probably the more creative and innovative. His writings were clear and concise, a model of what the analysis of vital statistics should be. Graunt therefore can justly be described as the founder of vital statistics.
JOHN M. LAST