(CNN) — The U.S. Postal Service delivered a $1.3 billion loss in the last three months of 2012.
The volume of first-class mail was down 4.5 percent, but shipping and package volume increased 4 percent.
In 2006, Congress mandated that the Postal Service pre-fund health care benefits for retirees. Since then, the USPS has been struggling, borrowing from taxpayers, and twice defaulting on loan payments.
Earlier this week, the Postal Service announced plans to end Saturday delivery in order to save money. Though it’s still unclear if the USPS can do that without Congress’ help.