Predicting a “Mature Population”: How Corporate Risk-Making Tools Popularized American Stagnation on the Eve of the Baby Boom

In 1938, the National Resources Board declared the United States to be on the road toward a “mature population.” The AT&T actuary responsible for modeling the first instantiation of the old age insurance component of Social Security worked from a similar premise. Predictions that the United States population would soon become older and also stagnant (or might even grow smaller) relied upon new demographic tools developed in and around life insurance corporations, especially Metropolitan Life whose Alfred Lotka and Louis Dublin first explained in 1925 how age structure data when combined with birth and death rates could be used to calculate the “true rate of natural increase” of the nation. This paper brings to light a brief moment in American history when the idea of biological stagnation enjoyed widespread acceptance. American historians have previously explored similar tropes of American economic maturity (and limited future prospects) coming out of the Great Depression, but the extent to which the nation’s biological future appeared tightly constrained has largely been lost. The first stirrings of the baby boom began the decline of the maturity thesis. In 1941, Life magazine—in an article coining the phrase “baby boom”— called into question what it saw as Hitler’s interpretation (echoing the demographers) of World War II as “an inevitable struggle between [Hitler’s] fertile German Reich and such sterile old nations as the U.S. and Great Britain.” Post-war tropes of American exceptionalism helped make the prior decades’ predictions of stagnation all but inconceivable. Yet predictions of maturity—even as they were quickly forgotten— left a powerful legacy in the structuring of the welfare state, in shaping debates over dealing with an aging nation, and in the popularization of statistical population forecasts.