Excel Pivot Question
 

I have a pivot table displayed with data populated using c# code.
I want to create a graph out of ONLY the FINAL summary rowS.
If I create a pivot chart, then it gets messed up if I expand the pivot table.
If I manually copy paste the sumary values into another place and draw a
graph based on that, then when the pivot table data is re-updated by c# code,
then my
graph would go out-of-sync.
If I refer to the summary cells somewhere and use that for the graphing,
then also when I expand/collapse the pivot table, then the location of the
summary rows change and so my graph goes blank.
One possibility is to get a handle of the summary rows using C# code, but
neither the PivotTable nor the PivotCache objects seem to be able to provide
any methods that return just the summary rows.

Any ideas?