public function execute()
 {
     list($start_date, $end_date, $group_by) = shopReportsSalesAction::getTimeframeParams();
     $checkout_flow = new shopCheckoutFlowModel();
     $stat = $checkout_flow->getStat($start_date, $end_date);
     $app_settings_model = new waAppSettingsModel();
     $this->view->assign(array('stat' => $stat, 'checkout_flow_changed' => $app_settings_model->get('shop', 'checkout_flow_changed', 0)));
 }