The funded status of the 100 largest corporate defined benefit pension plans dropped by $68 billion during July 2011, as measured by the Milliman 100 Pension Funding Index (PFI). The notable increase in the funded status deficit was primarily due to a substantial decrease in corporate bond interest rates that are the benchmarks used to value pension liabilities.
The funded ratio fell from 87.0% to 83.0% and the funded status deficit increased from $186 billion to $254 billion, the largest deficit increase of the year, and the 10th largest since the start of the Milliman 100 PFI in 2000.