Old Teachers, Old Ideas, and the Effect of Population Aging on Economic Growth

As populations age, the degree to which workers human capital reflects the cutting edge of technology falls because education took place further in the past. This “pure vintage” effect of aging is well known. In this paper, we explore a second effect of aging: in an older population, older teachers pass on knowledge that was current further in the past. We show that this “teacher multiplier” can significantly increase the technological backwardness of the labor force. We present both an analytic model that can be solved for steady states and a numerical model that can describe transitions in the average vintage of human capital as population age structure changes over time. We also discuss evidence on the effect of age on the technological up-to-dateness of workers in general and teachers in particular.