Stacked area chart with start and end dates

Hi,

I'm trying to create a stacked area chart from values that have a start date and an end date. I'd like the area to be drawn as a sum of the values at each x-axis date interval. So if I have data like:

Start              End               Value

2013-01-01      2015-01-01     100

2013-09-01      2014-01-01     200

2013-01-01      2016-01-01     300

What I need is to have the chart show the area y-axis at 400 from the start up to 2013-09-01 where it would rise to 600. At 2014-01-01 it would drop back down to 400 and at 2015-01-01 it would drop to 300 until the end.

Is this possible without calculating the sums for each date beforehand?