/**
  * Get the email CTOR report
  *
  * @since 4.1
  * @param null $fields unused
  * @return array
  */
 public function get_email_ctor_report($fields = null)
 {
     $report_data = array();
     $reports = FUE_Reports::get_top_emails_by('ctor', 50);
     foreach ($reports as $report) {
         $report_data[] = array('email_id' => $report['email_id'], 'clicks' => $report['clicks'], 'opens' => $report['opens'], 'ctor' => $report['ctor']);
     }
     return array('ctor' => apply_filters('fue_api_report_response', $report_data, $reports, $fields, $this->server));
 }