SQL rollup后排序问题

Question

CREATE TABLE tb(province nvarchar(10),city nvarchar(10),score int)
INSERT tb SELECT '陕西','西安',3
UNION ALL SELECT '陕西','安康',4
UNION ALL SELECT '陕西','汉中',2
UNION ALL SELECT '广东','广州',5
UNION ALL SELECT '广东','珠海',2
UNION ALL SELECT '广东','东莞',3
UNION ALL SELECT '江苏','南京',6
UNION ALL SELECT '江苏','苏州',1
GO

select case when grouping(province)=1 then '合计' else province end 省,
case when grouping(city)=1 and grouping(province)=0 then '小计' else city end 市,
sum(score) as 分数
from tb group by province,city with rollup

怎么对每个省份中的城市按分数进行排倒序