i am having real difficulties in trying to create a report where by a formula column can count down from a set number and show this subtracting a number from each row consecutively. so far the formula i am working on is -> 160.00 - advpm__Detail_Budget_c.advpm_Hours__c:SUM
this only subtracts each row from this nuber and not a count down from the first. although the sum at the end of the report is correct.
Please help if you can.