when did its theory develop?
17th century
Actuary
During the 17th century, a more scientific basis for risk management was being developed. 
what is an 'actuary'? A business professional who deals with the measurement and management of risk and uncertainty. what is its traditional employment requirements? Calculation skills, using sophisticated approximations called commutation functions, to facilitate timely, accurate, manual calculations of premiums. what are some early ones? Charitable operations; A small sum was paid into a communal fund on a weekly basis, and upon the death of a member, the fund would cover the expenses of rites and burial ; Non-life insurance
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Actuary [SEP] Development of theory
During the 17th century, a more scientific basis for risk management was being developed. In 1662, a London draper named John Graunt showed that there were predictable patterns of longevity and death in a defined group, or cohort, of people, despite the uncertainty about the future longevity or mortality of any one individual. This study became the basis for the original life table. Combining this idea with that of compound interest and annuity valuation, it became possible to set up an insurance scheme to provide life insurance or pensions for a group of people, and to calculate with some degree of accuracy each member's necessary contributions to a common fund, assuming a fixed rate of interest.