diff --git a/README.md b/README.md
index d852efa..a0b58cc 100644
--- a/README.md
+++ b/README.md
@@ -32,7 +32,7 @@ The rules:
- Do local function declarations affect performance?
- Do closures affect performance (vs. free functions)?
- For..of loop over Set vs. Array
-- For..of loop over Object.values vs. Map.forEach
+- For..of loop over Object.values vs. Map.forEach (large integer keys)
- Map vs. Object (lookup)
- Null or undefined? (equality check)
- Arguments passing: spread vs. call() vs. apply()