private function _apiDeleteFiles($config)
 {
     $defConfig = array('backup_id' => 0);
     $config = array_merge($defConfig, $config);
     $backup_id = $config['backup_id'];
     require_once JPATH_COMPONENT_ADMINISTRATOR . '/models/statistics.php';
     $model = new AkeebaModelStatistics();
     $model->setState('id', (int) $backup_id);
     $result = $model->deleteFile();
     if (!$result) {
         $this->status = self::STATUS_ERROR;
         $this->encapsulation = self::ENCAPSULATION_RAW;
         return $model->getError();
     } else {
         return true;
     }
 }