The nation’s largest defined benefit pension plans lost $49 billion in assets in January. Employers may have to double their contributions this year, according to the latest findings from the Milliman 100 Pension Funding Index released last Thursday.

January losses were offset by liability decreases of roughly $26 billion, resulting in a net loss of $23 billion in funding status for the month, according to Milliman. Pensions have lost 30 percent in funding status since the beginning of 2008, says John Ehrhardt, co-author of the Index.