Pensions may be provided for in a modern society by several methods, viz., voluntary individual savings, mandatory fully funded occupational pension systems, and mandatory social security financed by pay-as-you-go. The specific mixture of the three systems we will call the pension composition....

A model is presented that explains the mix between funded and unfunded pension systems. It turns out that total pension and the relative shares of the two systems may be explained and are determined by the population growth rate, technological growth, the time-preference discount rate, the...