diff --git a/data_utils_new_new.py b/data_utils_new_new.py
index c89ef78..0f41dfa 100644
--- a/data_utils_new_new.py
+++ b/data_utils_new_new.py
@@ -179,7 +179,7 @@ def _create_buckets(self):
             if idx_bucket != -1:
                 buckets[idx_bucket].append(i)
 
-        for i in range(len(buckets) - 1, 0, -1):
+        for i in range(len(buckets) - 1, -1, -1):
             if len(buckets[i]) == 0:
                 buckets.pop(i)
                 self.boundaries.pop(i+1)
@@ -269,3 +269,4 @@ def __len__(self):
         print(c.size(), spec.size(), y.size())
         #print(batch_idx, c, spec, y)
         #break
+