diff --git a/jest_rust/README.md b/jest_rust/README.md
index 21af281..978cc70 100644
--- a/jest_rust/README.md
+++ b/jest_rust/README.md
@@ -20,6 +20,8 @@ for_loops_forbidden_only: `987ms`
 
 trie creation and stats accumulation take 0ms
 
+FxHashMap faster than BTreeMap
+
 ## compile options benchmarks
 `lto` thin, fat doesn't change much