diff --git a/doc/conf.py b/doc/conf.py
index fd57ef46af..a678e6c206 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -41,7 +41,7 @@ def get_info():
         info['series'] = 'latest'
         info['branch'] = 'branch/default'
     else:
-        info['series'] = '.'.join(version.split('.', 2)[:2])
+        info['series'] = '.'.join(metadata['version'].split('.', 2)[:2])
         info['branch'] = 'branch/' + info['series']
 
     info['modules'] = [