Take the area of a plot and mark a percentage (based on volume)

[dkieran]

Hi

I have an area chart that has two series.

I first want to calculate the area of the graph, or more specifically I want to calculate the area within the two series lines.

I would then like to mark the point where it is 70% percent volume (of area) on the left and 30% vloume (of area) on the right.

I know how to calculate the area using the definate integral and also integrate it to 70% (or 0 to 0.7). What I cant do is mark the 70% percent point on the chart.

One series is positive and one is negative and they both travel towards zero on a polynomial curve as the x increases.

I have had a good look around and cannot find a solution

Thanks

 

[pgc01]

What I cant do is mark the 70% percent point on the chart.

Do you mean you want to draw a vertical line at that X value?

If that's the case, then Jon Peltier explains here how:

http://peltiertech.com/Excel/Charts/AddLineVertSeries.html