Pension plans saw a $7 billion decline in market value and a $1 billion increase in pension liabilities in November.

According to Milliman, Inc.'s Pension Funding Index, declining assets drove the deficit growth, but the 4.53 percent discount rate, the lowest in the study's 11-year history, is the big story.

"So long as we have low discount rates we'll have no choice but to hope for improved asset performance," said John Ehrhardt, co-author of the Milliman Pension Funding Study. "As 2011 draws to a close it seems increasingly likely that this will be a lost year for pension funding. In the coming weeks, plan sponsors will be closely monitoring both the discount rate and the market value of these assets, with the hope of starting off 2012 with at least some upward momentum."