/enums/asset_performance_label.proto 

--- v22/enums/asset_performance_label.proto 2026-01-23 15:36:20.000000000 +0000
+++ v23/enums/asset_performance_label.proto 2026-01-23 15:36:28.000000000 +0000
@@ -54,5 +54,9 @@

     // Best performing assets.
     BEST = 6;
+
+    // Performance label cannot be assigned to this asset. This may be because
+    // it's not used by asset based creatives.
+    NOT_APPLICABLE = 7;
   }
 }