Overviewing the findings: the Technical Panel Review of the Pension Insurance Modeling System*‡

The Pension Benefit Guaranty Corporation's (PBGC) Pension Insurance Modeling System (PIMS) is used to evaluate the financial security and resilience of the national program backstopping private defined benefit plans. The Pension Research Council of the Wharton School at the University of Pennsylvania recently convened a Technical Review Panel of experts to review key inputs, outputs, and model assumptions. Our review was intended to provide a formal evaluation of the technical adequacy of the model by outside experts. The papers herein summarize views of each expert on this project. Key findings are as follows: •The PIMS models are an important and valuable tool in modeling the Pension Benefit Guaranty Corporation's liability risk. To the best of our knowledge, there is no other model that can do a comparable job.•Nevertheless, some improvements could be integrated in the Agency's approach to modeling. Those deserving highest priority attention, in the experts’ view, include incorporating systematic mortality risk (i.e., treat mortality and longevity as stochastic variables); including new asset classes increasingly found in defined benefit plan portfolios (e.g., commercial real estate, private equity funds, infrastructure, hedge funds, and others); developing a more complex model for the term structure of interest rates; and incorporating an option value approach to pricing the insurance provided.•The Agency could also do more to communicate the range of uncertainty and potential for problems associated with the PBGC's financial status. This could include additional information including the conditional value-at-risk, and perhaps an ‘intermediate,’ ‘optimistic’, and ‘pessimistic’ set of projected outcomes, as well as the expected ‘date of exhaustion’ for assets backing pension benefits insured by the PBGC.