Weak investment performance and insufficient contributions will cause total unfunded liabilities for U.S. state public pensions to balloon by 40 percent to $1.75 trillion through fiscal 2017, Moody's Investors Service said in a report on Thursday.
The report comes amid increasing concern over America's ability to pay promised retirement benefits to public employees without draining state budgets.
It has been a tough year for the funds, which earned a median 0.52 percent on investments in fiscal 2016 versus their average assumed return rate of 7.5 percent, Moody's said.
In fiscal 2015, aggregate adjusted net pension liabilities stood at $1.25 trillion.
Half of U.S. states did not put enough money into their retirement systems in 2015 to curb the growth of unfunded liabilities. That held true even when states met the contribution levels their actuaries told them were necessary, Moody's found.
The nation's 100 largest public pensions were funded just below 70 percent as of June 30, according to a separate study on Thursday by consulting firm Milliman. That study found investment returns to be 1.31 percent and a funding deficit of $1.38 trillion.
Yet well-known problem spots - Illinois, New Jersey, Connecticut and Kentucky - are atypical, according to the Center for Retirement Research at Boston College.
Even when including debt and retiree healthcare costs, "the outlook at the state and local level is extremely heterogeneous," the researchers wrote in a brief this week. "A small minority face dire circumstances, but many jurisdictions appear to have their costs under control."