Defined-benefit pension plans lost $54 billion in assets in February, according to a new report from Milliman Inc., a consulting and actuarial firm.

The losses, however, were offset by liability decreases of roughly $21 billion, meaning a net loss of $33 billion in funding status for the month, based on its Milliman 100 Pension Funding Index, which consists of 100 of the nation’s largest defined-benefit pension plans.

In the last year, the funding ratio for these pensions has fallen from 99.6% to 71.7%.

“January was a terrible month for asset values, and February was worse,” said John Ehrhardt, co-author of the Milliman 100 Pension Funding Index. “We’re not even through the first quarter yet and already funding status had declined from 77.2% to 71.7%, and that’s with asset values being offset by changes in discount rates.”

Funding status has fallen by $337 billion in the last 12 months thanks in large part to a 26% decrease in asset return. At the end of February, the total asset value for these pensions stood at $869 billion.