The PBGC's single-employer pension program could face a $24 billion deficit by 2020, up 11% from its latest reported shortfall, while its multiemployer program's deficit will soar more than fivefold to $9.4 billion, according to the Pension Benefit Guaranty Corp.'s annual exposure report issued Thursday.

While the single-employer program did not show any risk of running out of money within the next 10 years, the multiemployer program has nearly a 30% chance of being broke within 20 years, according to the report.

The PBGC's deficit estimate uses its projections on the future status of private pension plans to gauge its own financial status. PBGC performed 5,000 future simulations for the single-employer program, based on the $21.6 billion deficit — $77.8 billion in assets to cover $99.4 billion in pension benefits — in the fiscal year ended Sept. 30, 2010, the most recent annual report available.

The multiemployer program had a $1.5 billion deficit — $1.6 billion in assets to cover $3.1 billion in pension benefits — in the same time period.

“Most private pensions are sound,” PBGC Director Joshua Gotbaum said in a statement, “but some are real sources of concern. We want to make sure they can restore themselves, and that PBGC has the resources to help.”

PBGC attributes the higher risk in the multiemployer program to a few large distressed plans, which they declined to identify.