‍As enslaved individuals crossed the Atlantic Ocean, death was inevitable due to outbreak of diseases, slaves taking their own lives, starvation, and thirst. The mortality of 15% is a minimum number that only accounts for deaths on the trans-Atlantic voyage itself. Captives continued dying after disembarkation because of diseases like dysentery and smallpox. These transits would continue on for some captives to other islands after the Danish West Indies, thus extending the journey at an even higher mortality rate.

The number of known deaths was not recorded for all voyages.