1. The terms death rate and mortality rate are sometimes used loosely and interchangeably. According to usage by demographers death rates are based on the average number of person-years at risk during a time period and mortality rates are based on the number at risk at the beginning of a time period. If there is little change in the number of persons at risk during the interval, the difference between the measures is small. Given the loading and unloading of slaves it is appropriate to use death rates as opposed to mortality rates in this paper. For a discussion of terminology
2. Mortality on Long-Distance Voyages in the Eighteenth Century;Riley;this Journal,1981
3. Deaths of Slaves in the Middle Passage;Cohn;this Journal,1985