diff --git a/src/pyWitness/DataProcessed.py b/src/pyWitness/DataProcessed.py
index ab47de6..983f724 100644
--- a/src/pyWitness/DataProcessed.py
+++ b/src/pyWitness/DataProcessed.py
@@ -658,8 +658,8 @@ def calculateConfidenceBootstrap(self, nBootstraps = 200, cl = 95, plotROC = Fal
         criterion              = _np.array(criterion)
         pAUC                   = _np.array(pAUC)
 
-        clHigh = 100.-(100.-cl)/2.0
-        clLow  = (100.-clHigh)/2.0
+        clHigh = 50.+cl/2.0
+        clLow  = 50.-cl/2.0
 
         cac_low                     = _np.percentile(cac,clLow,axis=0)
         cac_high                    = _np.percentile(cac,clHigh,axis=0)