public function getNumberOfAnswers($surveyId) {
        $fields['tokenCount'] = 'COUNT(DISTINCT gto_id_token)';
        $select               = $this->loader->getTracker()->getTokenSelect($fields)->andReceptionCodes([]);
        $select->forSurveyId($surveyId)
                ->onlySucces()
                ->onlyCompleted();
        $row                  = $select->fetchRow();
        return sprintf($this->_('Answered surveys: %d.'), $row['tokenCount']);
    }