The Labor Productivity Differential between the West Indies and West Africa: 1680-1830

This paper is an empirical test of Stefano Fenoaltea's (1999) hypothesis that the labor productivity differential between the Americas and West Africa was insufficient to cover the high mortality and transport costs of the forced transatlantic migration of slave labor. Using data on slave hire rates and slave subsistence costs in the West Indies from the mid-17th to the early 19th century, we measure surplus-to-subsistence ratios in the Americas and compare those measures to estimates of the surplus-to-subsistence ratios in Africa. Since there is almost no data on labor productivity in precolonial Africa, we impute surplus-to-subsistence ratios for Africa using estimates of fertility derived from the consensus view that the annual population growth in West Africa prior to the mid-19th century was 0.2% to 0.3%. We estimate the surplus-to-subsistence ratio required to maintain this population growth rate. By comparing an upper-bound estimate of the surplus-to-subsistence ratios of slave laborers in the West Indies to a lower-bound estimate for subsistence farmers in West Africa, we conclude that the labor productivity differential between West Africa and the West Indies was insufficient to cover the transport and mortality costs of the slave trade.