To whom it may concern

I am having problems calculating my sales commisson spreadsheet. I want a variable rate which is:

0-500 = 6%
501 - 4000 = 10%
4001+ = 12%

This is the easy part, however this is ongoin on a monthly basis and if a sales guys go over the threshold i want to pay them only on the amount over that threshold

ie a sales guy bills 400 in march and in april he does a further 200, therefore going over the 500 threshold, can excel work out that the commission due is 100 @ 6% and 100 @10% therefore making his commision 16.

i am really struggling

Make Thanks in anticipation

Tim