diff --git a/html/includes/print-graphrow.inc.php b/html/includes/print-graphrow.inc.php
index 9b98a8039..a35107b94 100644
--- a/html/includes/print-graphrow.inc.php
+++ b/html/includes/print-graphrow.inc.php
@@ -76,3 +76,4 @@ foreach ($periods as $period) {
         echo "</div>";
     }
 }
+unset($graph_array);