85% of public pension will go bankrupt, unless

... they earn a 9% rate of return.  Bridgewater associates released its own stress test of public pensions this week.  What it found is not pretty:

Public pensions have just $3 trillion in assets to invest to cover future retirement payments of $10 trillion over the next many decades, Bridgewater says. An investment return of roughly 9% a year is needed to meet those onerous obligations.

Unfortunately, they are expected to earn only 4%.  If this happens, 85% of them go bankrupt.