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8. Economists use a method called Total Factor Productivity (TFP) to assess technological change in the long-run. How is this method performed?

A. Economists plot the growth rate of a sample of countries against their initial income, and detect if there is a negative association

B. Economists perform interviews and surveys to Research + Development divisions in firms and universities and infer the degree of innovation

C. Economists subtract the difference in capital per worker in two moments in time, from the difference in productivity per worker in those moments. A positive value is indication of positive technological change

D.Economists analyze the technological index (Nasdaq) and estimate its capitalization ratio