With possibly serendipitous timing, Fitch Ratings released its latest bank ratings performance study late last week. The report used to go under the blunt but accurate title of the 'Bank Failure Study' but is now known as the 'Global Bank Rating Performance Study: Update 2015'.This latest study adds to the compilation of data and analysis of bank failures, defaults and rating transitions over a 26 year period. Fitch observed that bank failures have been correlated to financial crises with notable peaks in the 1990s and during the GFC.Fitch said the 2008-2009 peak represented a crisis that was truly global and for the first time included failures of large, highly rated banking groups. Moreover, failures in recent years were heavily weighted towards developed economies, with the Eurozone accounting for a significant number.The data showed that from 2012 to 2015, a total of 35 Fitch-rated banks failed, resulting in a one-year average failure rate of 1.06 per cent. Over the 26 years of the study, the one-year average failure rate is 1.6 per cent.Fitch noted that vast majority of the banks that failed between 2012 and 2015 had sub-investment grade viability ratings in the year prior to failure and, indeed, 27 of the 35 had ratings of 'b' or lower. The viability rating is the stand-alone rating of the bank before any allowance is made for likely state support, in need.It is state support that defines the difference between bank failure and bank default.Fitch said bank failure rates are five to six times that of bank default rates. Fitch expects to see the failure and default 'gap' close as resolution regimes become more commonplace and regulators position their banking systems to become less reliant on state support. NOTE: This item first appeared in the DCM Review.