diff --git a/script/fetcher.lua b/script/fetcher.lua
index 60440c7..6495907 100644
--- a/script/fetcher.lua
+++ b/script/fetcher.lua
@@ -56,7 +56,8 @@ this.callOverlayFunction = function(functionName, callback, name, parent, args)
     end
 
   -- flow statistics
-  elseif functionName == "get_flow_count" and (parent.object_name == "LuaFlowStatistics" or parent.object_name == "LuaItemProductionFlowStatistics") then
+  -- worst hack to validate that parent inherits from FlowStatistics
+  elseif functionName == "get_flow_count" and string.sub(parent.object_name, -14) == "FlowStatistics" then
 
     if args[2] == 'input' then isInput = true else isInput = false end
 
@@ -83,6 +84,11 @@ this.callOverlayFunction = function(functionName, callback, name, parent, args)
 
     end
 
+  elseif functionName == "get_flow_count" then
+
+    game.players[1].print("Cannot get_flow_count for unexpected instance of:")
+    game.players[1].print(parent.object_name)
+
   end
 
 end