diff --git a/src/views/dashboard/graphs/components/ColumnGraph.vue b/src/views/dashboard/graphs/components/ColumnGraph.vue
index 005ce37f..4eae8c89 100644
--- a/src/views/dashboard/graphs/components/ColumnGraph.vue
+++ b/src/views/dashboard/graphs/components/ColumnGraph.vue
@@ -135,7 +135,7 @@ limitations under the License. -->
       }
       return encodeURIComponent(label);
     }
-    return encodeURIComponent(metric);
+    return encodeURIComponent(metric || "");
   }
 </script>
 <style lang="scss" scoped>