diff --git a/htdocs/graph.class.php b/htdocs/graph.class.php
index 08df84f5c27..569be719134 100644
--- a/htdocs/graph.class.php
+++ b/htdocs/graph.class.php
@@ -80,6 +80,8 @@ class Graph
 
     $graph->SetVertTickIncrement(0);
 
+    $graph->SetDrawYGrid(1); 
+
     //
     if (strlen($title))
       {