Hi
I need a formula that works out commission on a cumalitive total which is
worked out in column M

0-25k 7%
25k - 50k 8%
50k - 75k 9%
75k - 150k 10%
150k - 250k 11%
250k - 500k 12%
500k+ 15%

What I have already tried does not work out correctly e.g If the first
invoice was for 30k (cumalitive total in M7) then I need the 1st 25k worked
out on 7% and 5k on 8%. My way works out the total amount on 8%.

Hope I have made myself clear

Any help would be appreciated
Thanks, Amanda