In January, the funded status of the 100 largest corporate defined benefit pension plans improved by $19 billion as measured by the Milliman 100 Pension Funding Index (PFI).

The funded status deficit narrowed to $148 billion from $167 billion at the end of December. As of January 31, the funded ratio rose to 91.0%, up from 89.7% at the end of December. January’s asset return of 3.35% was greater than any prior monthly asset return in 2018.

The market value of assets grew by $13 billion as a result of January’s robust investment gain. The Milliman 100 PFI asset value increased to $1.505 trillion from $1.459 trillion at the end of December.

The projected benefit obligation, or pension liabilities, increased to $1.653 trillion at the end of January. The change resulted from a decrease of 13 basis points in the monthly discount rate to 4.06% for January from 4.19% for December.