Some U.S. public pensions, which lack savings for $1.4 trillion of promises to retired government workers, will record wider gaps in fiscal years starting after July 1 because of changes in accounting rules.

Pensions in Illinois, Kentucky, Pennsylvania, and other states will see funded levels decline, in some cases by more than half, as they comply with new Governmental Accounting Standards Board rules that for the first time will require future pension costs to be included on balance sheets and change how they must calculate their underfunding.

The new rules won't affect the amount that states and municipalities actually owe, though they could prompt them to address their underfunding, said Dean Mead, research manager at the Norwalk, Connecticut-based board known as GASB, which makes accounting rules used by most governments. The changes may force some states to cut borrowing or spending.