Hawaii and several other states have retired public employees whose underfunded pensions are threatened.  That's according to a new study by the Virginia-based State Budget Solutions.  The report -- named "Promises Made, Promises Broken -- The Betrayal of Pensioners and Taxpayers,"  found that Hawaii's Employee Retirement System has nearly $27 million in unfunded liability. The state with the highest unfunded liability is Ohio to the tune of $287,373,800.  The study's authors say the report is an evaluation based on fair-market valuations that discounts liabilities at a risk-free rate, versus optimistic investment returns used by most plans.