diff --git a/contrib/perf.py b/contrib/perf.py
--- a/contrib/perf.py
+++ b/contrib/perf.py
@@ -1553,7 +1553,7 @@
         dist = opts[b'dist']
 
         if reverse:
-            beginrev, endrev = endrev, beginrev
+            beginrev, endrev = endrev - 1, beginrev - 1
             dist = -1 * dist
 
         for x in _xrange(beginrev, endrev, dist):