Have you tried searching the Microsoft Knowledge Base?
http://support.microsoft.com/kb/828678
may be relevant.

Jerry

butters14 wrote:

Does anyone know how to rank a group of numbers without having excel
give 2 alike numbers the lower value instead of splitting the
difference between the 2 tied values? Say I'm ranking A1:A12 and two of
the cells "tie" for highest value. Instead of giving each cell a rank of
11.5, excel gives both 11. Does anyone know a workaround for this issue?
I need the sum of the rankings to equal 1+2+3+4+5+6+7+8+9+10+11+12 and
everytime there is a tie i lose a unit. Please help. :)