diff --git a/AsbCloudInfrastructure/Services/DataSaubStatDrillingQualityService.cs b/AsbCloudInfrastructure/Services/DataSaubStatDrillingQualityService.cs
index f83932db..0d0322d4 100644
--- a/AsbCloudInfrastructure/Services/DataSaubStatDrillingQualityService.cs
+++ b/AsbCloudInfrastructure/Services/DataSaubStatDrillingQualityService.cs
@@ -127,7 +127,7 @@ public class DataSaubStatDrillingQualityService : IDataSaubStatDrillingQualitySe
         while (indexEnd < dataSaub.Count() - 1)
         {
             indexStart = Array.FindIndex(dataSaub, indexEnd, t => t.IdFeedRegulator == idFeedRegulator);
-            if (indexStart < 0)
+            if (indexStart < 0 || indexStart == dataSaub.Count() - 1)
                 break;
 
             indexEnd = FindIndexEnd(indexStart, idFeedRegulator, dataSaub);