This paper describes how stochastic population forecasts are used to inform and analyze policies related to government spending on the elderly, mainly in the context of the industrialized nations. The paper first presents methods for making probabilistic forecasts of demographic rates, mortality, fertility, and immigration, and shows how these are combined to make stochastic forecasts of population number and composition, using forecasts of the U.S. population by way of illustration. Next, the paper discusses how demographic models and economic models can be combined into an integrated projection model of transfer systems such as social security. Finally, the paper shows how these integrated models describe various dimensions of policy-relevant risk, and discusses the nature and implications of risk in evaluating policy alternatives.
Demography stochastic population forecast social security fiscal policy probability of solvency