Reuters The U.S. government has a $2.1 trillion surplus in unused funds that it owes to people who didn’t do their taxes, according to a report by the Government Accountability Office.

The surplus, the report said, was due to $1.1tn in “tax-deferred cash,” which is not subject to the income tax and therefore isn’t taxed when it is paid.

The GAO did not say how much of the surplus was in the form of cash and how much was held in accounts for investments.

The GAO audit, which examined tax returns filed by more than 30 million taxpayers from 2014 to 2021, found the vast majority of the cash, which the GAO called the “cash surplus,” was held by the government as investments and retirement accounts.

The cash was not taxed when the money was withdrawn and the GAOs analysis showed the cash surplus was only $3.5 trillion, not $2trillion as initially reported.

In all, the GAOC found, the cash is held in more than 100 retirement and investment accounts, including 401(k)s, retirement savings accounts, 403(b)s and 529(b), with the government estimated to hold about $1trillion.

It said the government had no information on how much money was held for retirement accounts, 401(ks), 403(bs), 529(bs)s or other accounts.

For example, the Government Accounting Office estimated the total amount of cash held in 401(b)(6) accounts was $1,085 billion.

The Office of Management and Budget (OMB) said the total value of the government’s retirement savings assets was $5.5trillion, but the GAOS said it was $2tn.

The Government Accounting Board said in a statement that the $2 trillion figure for retirement savings was “not reflective of the actual size of the program.”