rrautane

I thought to update this thread in case someone has this same problem as I did.

I was able to solve my problem with activeX componentcsXGraph.it allows scripted trend line drawing. Attached is a sample graph drawn with csXGraph with pretty much same values as in my first post.

This is not optimal solution as I don't like to use third party activeX controls. They may cause incompability problems in future. But at the moment this seems to be best way to achieve what I want. Let's hope Siemens will improve graphing capabilities in future.