Investment policies and risk sharing by corporate pensions

Using a corporate risk management model, we show that the investment risk sharing features of defined benefit corporate pensions help explain their aggressive investment policies as well as their diminishing popularity over time. For reasonable parameter values, the model successfully captures key empirical patterns including pension asset allocation and the relations among pension investment risk, corporate bankruptcy probability, and pension funding. Consistent with the observed trend, we find that switching from defined-benefit plans to defined-contribution plans enhances risk transfer and reduces firms' pension funding costs.