Because (i) such information (eg Inventory issues and returns) is often not provided in separate columns (though yours is!) but as positive and negative values all in the one column and (ii) the movement itself can be useful information, an alternative solution might be of interest.
With data as provided by @Al Everett, this would mean starting by combining columns
B, (as in
ColumnD in the example below where the column references have been shunted to the right to leave room, as in
ColumnA, for possibly more meaningful information for the transactions than that they happen to be on, say, your
Row4 - ie that these are for, say,
The movement (the net of your
B) is simply
A-B, or in the example, achieved with the formula:
D2 copied down as far as required.
E2 the formula:
will give the ‘running total’ (cumulative sum) when copied down as far as required. Because
D2 is a relative reference it will automatically increase: D2>D3>D4 etc when copied down.
D$2 however uses a fixed reference and will not change when the formula is copied down, meaning that the range to be summed will always start with the value in cell
D2, though always end with the value in
ColumnD for the respective row.