If you're still having trouble after reading through Ricksp's
#4 , could you post a sample of your data?
Something like this (how I initially interpreted your data):
[TABLE="width: 192"]
<colgroup><col width="64" style="width:48pt" span="3"> </colgroup><tbody>[TR]
[TD="width: 64, bgcolor: transparent"] [/TD]
[TD="width: 64, bgcolor: transparent"]
A[/TD]
[TD="width: 64, bgcolor: transparent"]
B[/TD]
[/TR]
[TR]
[TD="bgcolor: transparent"]
1[/TD]
[TD="bgcolor: transparent"]
RANK[/TD]
[TD="bgcolor: transparent"]
GRADE[/TD]
[/TR]
[TR]
[TD="bgcolor: transparent"]
2[/TD]
[TD="bgcolor: transparent"]
1[/TD]
[TD="bgcolor: transparent"]
5[/TD]
[/TR]
[TR]
[TD="bgcolor: transparent"]
3[/TD]
[TD="bgcolor: transparent"]
#N/A[/TD]
[TD="bgcolor: transparent"] [/TD]
[/TR]
[TR]
[TD="bgcolor: transparent"]
4[/TD]
[TD="bgcolor: transparent"]
2[/TD]
[TD="bgcolor: transparent"]
3[/TD]
[/TR]
[TR]
[TD="bgcolor: transparent"]
5[/TD]
[TD="bgcolor: transparent"]
3[/TD]
[TD="bgcolor: transparent"]
2[/TD]
[/TR]
[TR]
[TD="bgcolor: transparent"]
6[/TD]
[TD="bgcolor: transparent"]
4[/TD]
[TD="bgcolor: transparent"]
1[/TD]
[/TR]
</tbody>[/TABLE]
A2 Formula: =RANK(B2,$B$2:$B$6,0)