diff --git a/CHANGELOG.md b/CHANGELOG.md
index 57b12fe..2c2130f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,10 @@
 # Change Log
 
-## NOT RELEASED
+## 1.5.1
+
+### Changed
+
+- Improve parameter type and return type in phpdoc
 
 ## 1.5.0