diff --git a/oxdbarchive/model.py b/oxdbarchive/model.py
index 91d5159..f195c8f 100644
--- a/oxdbarchive/model.py
+++ b/oxdbarchive/model.py
@@ -71,7 +71,8 @@ class Archive(SQLObject):
       return True
 
   def sinceLastModification(self):
-    return time.time() - max([os.stat(f).st_mtime for f in glob('%s*/*'% self.basePath)])
+    lastModification = max([os.stat(f).st_mtime for f in glob('%s*/*'% self.basePath)])
+    return time.time() - lastModification
 
   def notifyFrontend(self, action, md5sum):
     if self.baseUrlFrontend: