diff --git a/html/includes/print-graphrow.inc.php b/html/includes/print-graphrow.inc.php
index 2403626327..c550910443 100644
--- a/html/includes/print-graphrow.inc.php
+++ b/html/includes/print-graphrow.inc.php
@@ -15,6 +15,7 @@ if($_SESSION['widescreen'])
 
 $graph_array['to']     = $config['time']['now'];
 
+$graph_data = array();
 foreach ($periods as $period)
 {
   $graph_array['from']        = $config['time'][$period];