Figuring out the Illinois government's backlog of unpaid bills isn't simple. It all depends on what you count and when you count it.

The most direct method is counting bills that state agencies have sent to the Illinois comptroller for payment.

By that measure, Illinois had $5 billion in unpaid bills as of Sept. 8. More than $1.4 billion were more than two months old.

That method doesn't count bills that aren't being sent to the comptroller. The Department of Healthcare and Family Services is simply sitting on about $1.9 billion in unpaid bills.

Illinois also owes about $1.7 billion for corporate tax refunds and employee health insurance premiums, two obligations that don't go through the comptroller.

By any measure, Illinois has a lot of bills to pay.