diff --git a/PxWeb/Mappers/SelectionResponseMapper.cs b/PxWeb/Mappers/SelectionResponseMapper.cs
index 907df2ec..8349930c 100644
--- a/PxWeb/Mappers/SelectionResponseMapper.cs
+++ b/PxWeb/Mappers/SelectionResponseMapper.cs
@@ -50,12 +50,12 @@ public SelectionResponse Map(Selection[] selections, List<string> heading, List<
 
             if (variable.CurrentGrouping != null)
             {
-                return variable.CurrentGrouping.ID;
+                return "agg_" + variable.CurrentGrouping.ID;
             }
 
             if (variable.CurrentValueSet != null)
             {
-                return variable.CurrentValueSet.ID;
+                return "vs_" + variable.CurrentValueSet.ID;
             }
 
             return null;