Not sure if this question should be in the WebGrid section.

I'm trying to create a Profit and Loss Statement type of presentation layout. The data rows will come from a dataset and there will be blank rows where Sub Totals, Gross Profit and Net Profit go.

From what I have seen so far, the WebCalcManager does calculations across the rows only? ie. such as 'add columns 1 and 2 and put it in column3'.

My question: How can I add data in certain rows in the same column ? For example, row 5 = rows 1 + 2 + 3, and row 15 = row 5 - row 12.

Can this be done with WebCalcManager? Or do I have to go for an accumulator type of solution - ie. where I have some arrays where I can accumulate selected values while looping through the dataset?

Also: I would prefer a solution which I can also use for a spreadsheet type of grid, so that the Sub Totals/Totals recalculate when a cell value is changed. I'm thinking, a recalc that triggers off on the client-side when a cell value is changed rather than a postback on the server-side, from a speed view point.

Thanks for reading, and thanks in advance for any ideas!