diff --git a/src/panel/graph_panel/controllers/analytic_controller.ts b/src/panel/graph_panel/controllers/analytic_controller.ts
index 4b7b14c..cd5eaae 100644
--- a/src/panel/graph_panel/controllers/analytic_controller.ts
+++ b/src/panel/graph_panel/controllers/analytic_controller.ts
@@ -584,7 +584,7 @@ export class AnalyticController {
         hsrSerie
       ];
     }
-    return hsrSerie;
+    return [hsrSerie];
   }
 
   get inspectedAnalyticUnit(): AnalyticUnit | null {