Crystal Reports Append letter to record number "special field"

Message

   Hi, 

Can anyone tell me if its possible to append letters to the record number within the special fields. So instead of 1 2 3 it would read RES1, RES2 etc?

Or would I need to create a formula which uses the record number?

Thanks

UPDATE: Cracked it, create a custom field and then insert formula = "RES" & " " & recordnumber

Edited by shabbaranks - 28 Oct 2013 at 2:07am