Accurate estimates of future populations are out of reach of present techniques; the methods actually used, however they are described, are extrapolations of past trends and cannot anticipate turning points in births or other components. The present paper is no exception. It summarizes the errors of past work in the expectation that these will indicate the accuracy of the figures here contained. The method used in this paper is to suppose some year in which each country will attain bare replacement (an average of about 2.3 children per fertile couple) along with a smooth transition to that condition, and a continuance of replacement until the age distribution stabilizes and the population becomes stationary. For most countries we took the turn of the century as about the time when replacement would be reached. Estimates of population and labor force are shown by age and sex at 25 year intervals for 150 countries; groupings are given by continent and degree of development. Printouts are available showing much more detail than we have been able to publish in this working paper
