This is a revised version of a paper presented at the annual meeting of the Population Association of America, Toronto, April 1972. The author is deeply indebted to the late Yoshiko Kasahara of the Dominion Bureau of Statistics for her continuous encouragement at the onset of this research project. He is also grateful to Robert Maheu and Madeleine Rochon-Lesage for general assistance, and especially to Pierre Beauchamp for his programming assistance which involved dealing with very tricky coded magnetic tapes. Finally, he wishes to thank Judith Blake Davis, Beatrice Keyfitz, Pierre Fortin, Jacques Henripin, and Etienne Van de Walle for their most helpful comments and suggestions on an earlier draft of this article. The research project was supported by the Canada Council and data were processed on the University of Montreal CDC 6400 computer.