Five Facts You Need to Know About Technology Diffusion

This paper presents a new data set on the diffusion of about 115 technologies in over 150 countries over the last 200 years. We use this comprehensive data set to uncover general patterns of technology diffusion. Our main 5 findings are as follows: (i) Once the intensive margin is measured, technologies do not diffuse in a logistic way. (ii) Within a typical technology, the dispersion in the adoption levels across countries is about 5 times larger than the cross-country dispersion in income per capita. (iii) The rankings of countries by level of technology adoption are very highly correlated across technologies. (iv) Within a typical technology, there has been convergence at an average rate of 4 percent per year. (v) The speed of convergence for technologies developed since 1925 has been three times higher than the speed of convergence for technologies developed before 1925.