Despite a tripling in the value of the S&P 500 index since July 2009, Illinois' pension shortfall has worsened by 75 percent during the same period. 

In 2009, the shortfall in Illinois' five state-run funds stood at "just" $78 billion. Today, the funding hole is at a record $137 billion, a $59 billion increase. That's according to preliminary actuarial reports recently released by the state pension funds.

The warning this trend provides is stark: if pension debts in Illinois continue to grow during a period of remarkable stock market returns, imagine how those funds will fare when the next recession inevitably hits.