Robert W. Fogel (born 1926) is best known as the leading proponent of revisionistic economic analysis of some of the most cherished assumptions of American history. Dubbing his technique “”cliometrics,”” Fogel introduced cost/benefit analysis, depreciation, and value added considerations into the area of historical study. In 1964, in his book Railroads and American Economic Growth, Fogel attacked the commonly-held notion that the development of the railroad network was a turning point in the economic development of the United States. A decade later, Fogel raised a storm of controversy with his book Time On The Cross: The Economics of American Negro Slavery, in which he concluded that slavery was a far more profitable economic institution than had been previously thought.