The government added $5.3 trillion in new financial obligations in 2010, largely for retirement programs such as Medicare and Social Security. That brings to a record $61.6 trillion the total of financial promises not paid for.
This gap between spending commitments and revenue last year equals more than one-third of the nation's gross domestic product.
Medicare alone took on $1.8 trillion in new liabilities, more than the record deficit prompting heated debate between Congress and the White House over lifting the debt ceiling.
Social Security added $1.4 trillion in obligations, partly reflecting longer life expectancies. Federal and military retirement programs added more to the financial hole, too.
Corporations would be required to count these new liabilities when they are taken on — and report a big loss to shareholders. Unlike businesses, however, Congress postpones recording spending commitments until it writes a check.