Bowen, Leamer, and Sveikauskas tested the Heckscher-Ohlin theory by comparing the ratio of a country's endowment of a factor to each country's share of world income. Assuming the factor proportions theory is correct, a country whose factor share exceeded their income share would be an exporter of that factor. For two-thirds of the factors tested, trade ran in the predicted direction less than percent of the time