diff --git a/lib/s3Helper.js b/lib/s3Helper.js
index ed73562..efc7f8e 100644
--- a/lib/s3Helper.js
+++ b/lib/s3Helper.js
@@ -82,8 +82,8 @@ module.exports.parseS3Key = function (key) {
 }
 
 function compareS3Key (a, b) {
-  const recordPartIndexA = a.Key.substring(47).split('/')[2]
-  const recordPartIndexB = b.Key.substring(47).split('/')[2]
+  const recordPartIndexA = a.Key.substring(47).split('/')[1]
+  const recordPartIndexB = b.Key.substring(47).split('/')[1]
   if (recordPartIndexA < recordPartIndexB) {
     return -1
   } else if (recordPartIndexA > recordPartIndexB) {