diff --git a/TdlpackIO.py b/TdlpackIO.py
index 9a6230a..929cfba 100755
--- a/TdlpackIO.py
+++ b/TdlpackIO.py
@@ -121,7 +121,7 @@ def _get_index(self):
                     self._index['size'].append(temp[1])
                     self._index['type'].append('data')
                     self._index['date'].append(temp[6])
-                    self._index['lead'].append(int(temp[9]-((temp[9]/1000)*1000)))
+                    self._index['lead'].append(int(str(temp[9])[-3:]))
                     self._index['id1'].append(temp[7])
                     self._index['id2'].append(temp[8])
                     self._index['id3'].append(temp[9])
@@ -176,6 +176,8 @@ def _get_index(self):
                 break
 
         self._hasindex = True
+        self.dates = tuple(sorted(set(self._index['date'])))
+        self.leadtimes = tuple(sorted(set(self._index['lead'])))
 
     def close(self):
         """
diff --git a/test/test_tdlpackio_iter.py b/test/test_tdlpackio_iter.py
index 192ee03..cb0b967 100755
--- a/test/test_tdlpackio_iter.py
+++ b/test/test_tdlpackio_iter.py
@@ -22,6 +22,8 @@
 # Open vector TDLPACK file; iterate; close
 # ---------------------------------------------------------------------------------------- 
 f = TdlpackIO.open("sampledata/hre201701.sq")
+print(f.dates)
+print(f.leadtimes)
 f.seek(0)
 for rec in f:
     print(f.recordnumber,type(rec),rec.id)
@@ -31,6 +33,8 @@
 # Open gridded TDLPACK file; iterate; close
 # ---------------------------------------------------------------------------------------- 
 f = TdlpackIO.open("sampledata/gfspkd47.2017020100.sq")
+print(f.dates)
+print(f.leadtimes)
 f.seek(0)
 for rec in f:
     print(f.recordnumber,type(rec),rec.id)