Need Score to update from a different column of data each week

I have a data page where suppliers enter their data for the week. Each week they will get a differnt score based on what they enter. for example (=IF(P20="N/A","Reference",IF(P20>(AA34*1.15),"×",IF(P20>(AA34*(1.05)),"Û","Ù"))) this will show a Circle, Triangle or X.
How can I show the score each week on the chart. The chart actually has about 3 months of weekly data. But I only want that week "score" to show.