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Population aging and PAYG pensions in the OLG model


This paper shows the effects on a pay-as-you-go pension system of the demographic change in the standard overlapping generations model. Firstly, we consider a setting with exogenous fertility and then a model with endogenous fertility. In both cases, population aging due to increased longevity implies a reduction in pensions payouts.

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  1. Although this is an obvious limitation of our theory, it allows us to compare the results with those obtained by the large literature working with the “canonical” overlapping generations model.

  2. A well-known empirical regularity of growth is that the capital share in added value, α, is about one third.

  3. Similar results have been obtained by Fanti and Gori (2008). However, in that paper, the child-rearing cost was not considered, while here it affects negatively both k  ∗  and p  ∗ .

  4. In a similar setting, a discussion paper by Fanti and Gori (2009) assumes a fixed cost of child rearing. Here, instead, the time cost of child rearing introduces an additional negative substitution effect on fertility following an increase in longevity.


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Correspondence to Giam Pietro Cipriani.

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Responsible editor: Alessandro Cigno

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Cipriani, G.P. Population aging and PAYG pensions in the OLG model. J Popul Econ 27, 251–256 (2014).

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  • PAYG pensions
  • Fertility
  • Longevity

JEL Classification

  • J13
  • H55