diff --git a/API.md b/API.md
index 29696a3..8d3fba9 100644
--- a/API.md
+++ b/API.md
@@ -610,7 +610,7 @@ this:
 
 ```js
 xaxis: {
-    mode: "time"
+    mode: "time",
     timeformat: "%Y/%m/%d"
 }
 ```