Drug store promotions can look simple on the planning calendar. The buyer agreement is approved. The ad event is scheduled. The endcap is planned. The temporary price reduction is set. The supplier accrues the allowance and expects the math to work. Then the deductions arrive. That’s when the clean promotional plan starts to look a lot more complicated. For suppliers selling to CVS, Walgreens, and similar drug retailers, promotional deductions can be hard to reconcile because