diff --git a/stats/atoms.proto b/stats/atoms.proto
index 18a0ab0..bd61f3c 100644
--- a/stats/atoms.proto
+++ b/stats/atoms.proto
@@ -11272,4 +11272,5 @@
     }
     optional ResultType result_type = 2;
     optional int64 latency_millis = 3;
+    optional string session_id = 4;
 }