Pivot table query: How to produce cumulative data?

I'd like to create a chart that shows how long it took for us to hit a target. My data is simply 'input date' and 'document value' and i'd like to plot the cumulative position against the target. The target will be plotted on the y axis as a horizontal line across the chart and the cumulative position will be shown growing on the x. The problem I have is that I can't obtain the cumulative figures to plot. If I throw the data into a pivot table and then show the values as a running total in the input date it only shows the cumulative position per day i.e. if three invoices were raised on 29/08/12 at £1k a piece the cumulative position will be £3k, if no invoices are raised today (30/08/12) the cumulative position will be £0k.

How can I amend the pivot table to show the true cumulative position? Or how can I create a separate data table (using formulas?) to show the plotable data I require?

Thanks,

Snook

a running total oughta work-see attached file

you've got the major unit for the axis set to 14 days-change it to one month

you're welcome. never be afraid to share the love ;-)