I am trying to rank a string of 5 numbers giving each rank a score depending
on their effort. The problem I have is that some efforts have a 0, yet the
rank function still gives them a value of at least 1.

Example

Alpha 5
Bravo 0
Charlie 4
Delta 1
Echo 3

The result would be:
Alpha - rank 1
Charlie - rank 2
Echo - rank 3
Delta - rank 4
Bravo - rank 5

How can I tell the command to, if it sees a 0, award it a 0 ranking?