Sizing Bubble relatively by column

[#1]

Hello, I have a grid of bubbles. The x categories have different maxima and many of the bubbles are not larger than a pixel as the larger bubbles have priorty and the bubble appear to be sized relative all grid values. So, I'm trying to calculate the maximum of each column ( x category). After I accomplish that, I need to size all relatvely that by the max in the appropriate column.

Thanks