diff --git a/README.md b/README.md
index 4b9d52b..cadbdc9 100644
--- a/README.md
+++ b/README.md
@@ -133,7 +133,7 @@ Structure of each item which got from items() function.
   <tr>
     <td>currency</td>
     <td>str</td>
-    <td>ex. "USD"</td>
+    <td>ISO 4217 currency codes (ex. "USD")</td>
   </tr>
   <tr>
     <td>bgColor</td>