On latitude and affluence: The equatorial grand canyon

Our objective is to explain per capita GDPs by the countries' latitude, using PPP-based data for 138 countries in 1985 (PPP = purchasing power parity). A simple approach is formulated which nevertheless accounts for as much as two-thirds of the variance of the per capita GDPs.Theil is the McKethan-Matherly Eminent Scholar Emeritus and Courtesy Professor of Food and Resource Economics, while Galvez is an Associate in Research of the Bureau of Economic and Business Research, both at the University of Florida (UF). We thank Sri Devi Deepak, Charles B. Moss and James L. Seale of the UF Food and Resource Economics Department for helpful discussions and Robert Summers of the University of Pennsylvania for making the data available to us.