Special data source ?

[Dany]

Hi,

here is my problem.
I made some graphs wich represents the sum of traffic for several interfaces (up to 12) and I need to calculate the 95th Percentile for the sum of traffic.
Actually the 95th percentile is based on the data source with highest value.
So my question is :
is it possible to create a data source wich is the sum of several data sources in order to apply the 95th Percentile on it ?
I hope that it is clear.

Thanks for your help !