Sex and age characteristics exist for 111,323 Africans carried across the Atlantic or close to more than one-tenth of all Africans who left for the Americas on British ships between 1663 and 1714. Traders took these slaves from every major African region involved in the traffic at this time, except for southeast Africa, and carried them to mainly Caribbean destinations on a total of 432 ships – 361 operating from English ports, 46 from Dutch, 22 from Danish, and 3 from French. The sample is thus large and well distributed. The major bias is the lack of observations for Brazil and the fact that the English slave trader and the English Caribbean are overrepresented. However, it is likely that the English carried more slaves than all other nationalities combined in these years and that the English Americas absorbed more slaves than all other transatlantic regions. Mean number of Africans per ship in the sample is 257.7 (s.d. = 152.3).

Three preliminary comments are called for. The counts of men, women, and children or males and females included in the sample were sometimes made before the ship began its journey, sometimes at the point of arrival or point of sale, and sometimes at all three locations. The possibility arises that mortality between these points was age- or sex-specific and that demographic ratios on board ships leaving Africa would not be the same as on those arriving or sold in the Americas.