I'm developing a C# application that creates a scatter/line chart in a
PowerPoint presentation.  I need to populate the chart's datasheet with
12,000 data points.  I can do it one cell at a time, but this approach is far
to slow.

As far as I can tell, the only other options are to use the Paste or
ImportData methods of a range object.  I have not attempted the ImportData
method because I would rather not have to create an intermediate file.  I
have attempted to use the paste method, but it always throws a "Paste
operation failed" error.  Here is a code snippet:

// populate an array of data (1000 data points per row)
int rowCount = 1000;
float [] probability = new float[rowCount];
for (int i=0; i < rowCount; i++)
{
   probability[i] = ((float)(i+1)) / (((float)rowCount)/100.0f);
}

// Call my custom object to get an instance of PowerPoint
application = MSOfficeApp.GetPowerPointInstance();

// Create a new presentation
presentation = application.Presentations.Add(MsoTriState.msoTrue);

// Create a slide
PowerPoint.Slide slide = _presentation.Slides.Add(1,
PowerPoint.PpSlideLayout.ppLayoutBlank);

// Create a chart
Graph.Chart graphChart = (Graph.Chart)
slide.Shapes.AddOLEObject(50,50,640,480,"MSGraph.Chart.8", "",
MsoTriState.msoFalse, "", 0, "",
MsoTriState.msoFalse).OLEFormat.Object;

// Create a datasheet
Graph.DataSheet datasheet = graphChart.Application.DataSheet;

// Create a range 1 column by 1000 rows
Graph.Range r = (Graph.Range) datasheet.get_Range(datasheet.Cells[2,1],
datasheet.Cells[rowCount+1,1]);

// Copy the array to the clipboard
Clipboard.SetDataObject(probability);           

// Paste from clipboard to range in datasheet
r.Paste(false);

I haven't been able to find a useful reference/examples for using
Microsoft.Office.Interop.Graph, so any suggestions would be appreciated.  
Also, any helpful pointers on using the ImportData method would be
appreciated, as it may be my fallback solution.