Report column total in chart

Hello,

I need to show on a report (and consequent dashboards showing that report), the total for each column.

I have this report in which i show the SUM: Value, where "Value" is a decimal field, grouping by assigned user and month:

In the chart i can clearly see the total for each sub-group, but I can't see the total for each column (group of two fields).

Is there a way to show that total?

Thanks