From 2009 to 2016, the gap between how much the state of Michigan has saved and how much it needs to cover pension promises made to school employees and retirees has grown by $17.1 billion. The pension system’s unfunded liability was $12.0 billion in 2009, and it rose to $29.1 billion in 2016.

How much is $17.1 billion? It's enough to give each of the state’s 95,000 public school teachers a $180,000 bonus.