Wheat Prices and Rainfall in Western Europe

Abstract

THE paper which I have the honour of reading to you to-night is ill substance a sequel and supplement to an article on " Weather " and Harvest Cycles," published in the Economic Journal of December, 1921.In that article (which I shall refer to here as " my former article ") I gave index-numbers of wheat prices in Western and Central Europe from 1500 to 1869 and the preliminary results of an analysis of these figures, by mathematical and arithmetical methods, with a view to discovering periodicity.I summarized my conclusions on this point " in three propositions of a "descending order of certainty ": First, the yield of harvests in Western and Central Europe from the middle of the sixteenth to the opening of the twentieth century has been subject to a periodic influence, or combination of such influences, tending to produce bad harvests at intervals of about 15-3 years, the first epoch falling in 1556.This proposition is about as certain as harmonic analysis can make it.Second, this period of 15*3 years, though corresponding to certain physical facts, is not a permanent one, but arises from a temporary combination of two or more shorter cycles.This proposition, though not certain, is in both of its branches highly probable.