Balancing Machine to a Target Percentage

Im trying to balance Machine Center A to a target percentage based on the total uptime hours. So I have pounds and tph to calculate the hours required and if my hours required are over the target percentage I manually adjust the loading in column K and L to the other machine in the highlighted cells. What I'd like to happen is create a if statement that says if greater than 75% subtract .01 until target is met, else add .01. My problem is I keep getting a circular reference. Hopefully I can get some help with this loading.