IF函数问题

问题描述:

IF函数问题
=IF(C2>=95,"A",IF(C2>=90,"AB",IF(C2>=80,"B",IF(C2>=70,"C",IF(C2>=0,"D",IF(C2="未供货","未供货"))))))
如何当C2=未供货,我希望下面也输出个未供货,但是一直输出的是A,

=IF(C2="未供货","未供货",IF(C2>=95,"A",IF(C2>=90,"AB",IF(C2>=80,"B",IF(C2>=70,"C",IF(C2>=0,"D"))))))