. under the extremely unlikely scenario of simultaneous default by every clearing firm who has open positions with unrealized losses , the maximum exposure related to cme 2019s guarantee would be one half day of changes in fair value of all open positions , before considering cme 2019s ability to access defaulting clearing firms 2019 performance bond and guaranty fund balances as well as other available resources . during 2010 , cme transferred an average of approximately $ 2