Wharton Pension Research Council Working Papers

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Working Paper

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The Pension Benefit Guaranty Corporation (PBGC)’s Pension Insurance Modeling System (PIMS) model has taken on the Herculean task of modeling in detail and under many scenarios the cash outflows associated with the pension obligations they have assumed. This paper’s comments are focused almost entirely upon PBGC’s termination liabilities, and address four pressing issues: (1) the need to discount the liability stream by current riskless interest rates instead of using corporate bond rates that reflect credit risk, call risk, and other risks, or using some ad hoc prescribed average of past rates; (2) the need to use a term structure of interest rates; (3) the need to employ more useful investment management benchmarks; and (4) how to implement a relevant and rigorous liability benchmark.

Working Paper Number



The research reported herein was pursuant to a grant from the U.S. Social Security Administration (SSA) funded as part of the Retirement Research Consortium (RRC); the author also acknowledges support from The Pension Research Council at The Wharton School. The author is grateful for helpful discussions with Olivia Mitchell and Mark Meyer. However, all findings and conclusions expressed are solely those of the author and do not represent the views of the SSA or any agency of the federal government, the MRRC, the PRC, The Wharton School at the University of Pennsylvania, or Charles River Associates.

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Economics Commons



Date Posted: 26 June 2019