diff --git a/asyncua/common/node.py b/asyncua/common/node.py
index bbda9e54d..4123f61f7 100644
--- a/asyncua/common/node.py
+++ b/asyncua/common/node.py
@@ -567,7 +567,7 @@ async def read_processed_history(self, aggregate_type, aggregation_configuration
             details.AggregateConfiguration = ua.AggregateConfiguration(aggregation_configuration)
             details.ProcessingInterval = processing_interval
             d0 = []
-            for i in aggregtype :
+            for i in aggregate_type :
                 d0.append(ua.NodeId(i))
             details.AggregateType =d0