Report with stacked bar - weeks of months

Hi,

I am trying to build a report where the result would be a chart where in the bottom would be the weeks of a month, i.e. 1-5, and in the bars stacked the different months' values. So for example, I want to know the predicted sales of week 1 of each month stacked in one bar, so I would know how the sales prediction evolves in different weeks of the month over a few months ahead. Is this even possible? I have managed to get the formulas right in each column, but I have no idea how to get each