Mysql查询结果中如何保留两位小数?

set @day:= "2021-3-27";
SELECT @day as 统计日期,供应商, 
round((上年结转+发票_1+发票_2+发票_3+发票_4),2) AS 开票总计, 
round((付款_1+付款_2+付款_3+付款_4),2) AS 付款总计, 
round((上年结转+发票_1+发票_2+发票_3+发票_4-付款_1-付款_2-付款_3-付款_4),2) AS 欠款总计 
FROM 欠款
WHERE (上年结转+发票_1+发票_2+发票_3+发票_4-付款_1-付款_2-付款_3-付款_4)<>0
ORDER BY 欠款总计 desc;