diff --git a/src/OrderReportsListBuilder.php b/src/OrderReportsListBuilder.php
index 8829f08..af44f9e 100644
--- a/src/OrderReportsListBuilder.php
+++ b/src/OrderReportsListBuilder.php
@@ -18,7 +18,7 @@ class OrderReportsListBuilder extends EntityListBuilder {
     $header['amount'] = $this->t('Amount');
     $header['tax_amount'] = $this->t('Tax amount');
     $header['shipping_amount'] = $this->t('Shipping amount');
-    return parent::buildHeader() + $header;
+    return $header + parent::buildHeader();
   }
 
   /**