public static function paidAmount($request, $match)
    {
        $model = new Bank_Receipt();
        $params = array(
            'select' => 'SUM(amount) AS amount',
            'filter' => array(
                'payRef IS NOT NULL',
                'payMeta IS NOT NULL'
            )
        );
        $result = $model->getList($params);
        return $result[0]->amount;
    }