diff --git a/README.md b/README.md
index a9ad4b3..7e603e2 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,7 @@ $cache = new FileCache;
 
 $updatedTime = $cache->refresh('updatedTime', function () {
     return date("H:i:s");
-});
+}, 60);
 
 echo "Updated time: {$updatedTime}";
 ```