I am trying to figure out how to create a worksheet that has several
colums (that are important to this issue)
They are called PurchaseAmount, SlidingPercent, CommisionsPaid

What I need to do, is to have the slidingpercent, adjust based on the
amount of the sum of commissionpaid (basically,
=if(sum(commisionedpaid15000,0,28) -if I have accumilated more than
15000, then my percentage split is 0, up until that point, it is 28%

When I entered the formula, I get 0 for the percent and then the
commisionpaid turns to 0. I have tried to put the sum of the
commisionedpaid, into a different cell, and then referred to that cell
in the formula, but I then got a cyclic error (which it was)

Each row is a new transaction. I would need to make sure that previous
entries are not effected when the total of the column beem totalled


How can I perform this?