Modify the totalerrorcount field in the definition's query:  
 
totalerrorcount= sum(isnull(CTHH.ErrorCountToHalf,0))  + sum(isnull(CTHH.IncompleteCallsHalf,0)) + sum(isnull(CTHH.AgentErrorCountToHalf,0))  + sum(isnull(CTHH.ServiceLevelErrorToHalf ,0))  
 
Depending on how the SL is configured for the call types (i.e. ignore, positive, negative (default)):  
 
SL Footer Formula (if SLA Negative): SUM(${ServiceLevelCalls}) / SUM(${ServiceLevelCallsOffered})  
 
SL Footer Formula (if SLA Abandon Ignore): SUM(${ServiceLevelCalls}) / (SUM(${ServiceLevelCallsOffered}) - SUM(${ServiceLevelAband}))  
 
SL Footer Formula (if SLA Abandon Positive): (SUM(${ServiceLevelCalls}) + SUM(${ServiceLevelAband})) / SUM(${ServiceLevelCallsOffered})    
 
SL Footer Formula (if SLA Abandoned Ignore and ERRORS excluded): SUM(${ServiceLevelCalls}) / (SUM(${ServiceLevelCallsOffered}) - SUM(${ServiceLevelAband}) - SUM(${totalerrorcount}))  
 
SL Footer Formula (if SLA Abandon Positive and ERRORS included): (SUM(${ServiceLevelCalls}) + SUM(${ServiceLevelAband}) + SUM(${totalerrorcount})) / SUM(${ServiceLevelCallsOffered})