In April, the funded status of the 100 largest corporate defined benefit pension plans decreased by $10 billion as measured by the Milliman 100 Pension Funding Index (PFI). The deficit swelled to $257 billion from $247 billion at the end of March. As of April 30, the funded ratio fell to 84.9%, down from 85.3% at the end of March.

April’s 0.84% investment return increased Milliman 100 PFI asset values by $7 billion to $1.441 trillion from $1.434 trillion at the end of March.

The projected benefit obligation increased by $17 billion during April, raising the Milliman 100 PFI value to $1.698 trillion.

Over the last 12 months (May 2016-April 2017), the cumulative asset return for these pensions has been 8.95% and the Milliman 100 PFI funded status deficit has improved by $139 billion. The primary reason for the increase in funded status has been investment returns above expectations.