Do you want to add a running balance to the above report?
Such that you get these figures for the first 6 records?
23 (8 + 15)
32 (23 + 9)
6 (balance starts over)
16 ( 10 + 6 )
22 ( 16 + 6 )
If so, and assuming that each row of data in your example represents one record..
Define a field of type summary and specify that it compute the total of Balance. Specify that this be a running total and then select "Restart Summary with each sorted group" and select the date field shown in your sub headings as the "when sorted by" field.