The problem of persistence in economic-demographic cycles

A continuous model for population cycles developed by Frauenthal is extended to provide further insights into damping and persistence. Values of the cycle magnitude parameter γ which would yield persistent cycles are estimated for a number of populations, and a regression technique is introduced by which γ can be estimated directly from cohort fertility rates. The results imply that cycles in American and other Western fertility since the depression, if present, have been stabilizing in their effects.