If A2:A8 consists of 0's, empty cells, and positive numbers:

B2, copied down:

=IF(A20,RANK(A2,$A$2:$A$8),"")

The following expensive formula should yield the same ranking as the
foregoing:

=IF(A20,SUMPRODUCT(--($A$2:$A$8A2),--ISNUMBER($A$2:$A$8))+1,"")


JA wrote:
Is it possible to set the "rank" formula to overlook zeros?