diff --git a/commerce_flat_rate.module b/commerce_flat_rate.module
index 07a56a3..1dd8f6a 100644
--- a/commerce_flat_rate.module
+++ b/commerce_flat_rate.module
@@ -129,7 +129,7 @@ function commerce_flat_rate_commerce_shipping_service_info() {
       );
 
       // Unserialize the data array for the service.
-      $data = !empty($service['data']) ? unserialize($service['data']) : '';
+      $data = !empty($service['data']) ? unserialize($service['data']) : array();
 
       $price_component_type = 'flat_rate_' . $name;
 
@@ -198,6 +198,7 @@ function commerce_flat_rate_service_new() {
       'currency_code' => commerce_default_currency(),
       'data' => array(),
     ),
+    'data' => array(),
     'is_new' => TRUE,
   );
 }
diff --git a/includes/commerce_flat_rate.admin.inc b/includes/commerce_flat_rate.admin.inc
index cdcf181..40f18f2 100644
--- a/includes/commerce_flat_rate.admin.inc
+++ b/includes/commerce_flat_rate.admin.inc
@@ -210,7 +210,7 @@ function commerce_flat_rate_service_form_submit($form, &$form_state) {
   if (!empty($form_state['values']['flat_rate']['include_tax'])) {
     $shipping_service['data']['include_tax'] = $form_state['values']['flat_rate']['include_tax'];
   }
-  else {
+  elseif (!empty($shipping_service['data']['include_tax'])) {
     unset($shipping_service['data']['include_tax']);
   }