Suppose that we receive 4% net handling charges of nominate, that 4% should be free of any discount, rebate, retro, deduction, etc. That would be fair to us.
If this is the case, 4% should add back 7.5% to offset such cost. ie. 4%*1.075 = 4.3%.
As in the cost factor list out below, the cost of finance for the nominate items is about 1.6% to 2%. The total handling charges to Boots becomes 5.9% to 6.3%. It means that we pay more than we get from Boots.