Stacked bar chart colors

Hello,

In my report, I have the field 'Year' -- as Dimension

and Measure is Sum({<[BranchID] = p({<[Year]= {"$(=Max(Year) - 1)"}>})>}[FactSoldAmount]) (using this formula, I calculate the sum of the same companies in different years) .

In this formula I don't use the new branches that was added this year. I want to have a bar chart like in this picture, where new companies will be shown in different colours

How can do it?