diff --git a/pg_stat_monitor.h b/pg_stat_monitor.h
index da18296..22a5a38 100644
--- a/pg_stat_monitor.h
+++ b/pg_stat_monitor.h
@@ -152,10 +152,10 @@ typedef enum pgsmStoreKind
 	PGSM_EXEC,
 	PGSM_STORE,
 	PGSM_ERROR,
-
-	PGSM_NUMKIND				/* Must be last value of this enum */
 } pgsmStoreKind;
 
+#define PGSM_NUMKIND	(PGSM_ERROR + 1)
+
 /* the assumption of query max nested level */
 #define DEFAULT_MAX_NESTED_LEVEL	10