[Xymon] Change default RRD graph definitions

Hello,

I'm looking to change the graph definitions for one of the built-in checks e.g. [http].

The default creation method for the RRD graphs is "average", but I want to display the "last" value instead. The graphs.cfg file has this to create http graphs:

[http]

DEF:p at RRDIDX@=@RRDFN@:sec:*AVERAGE* LINE2:p at RRDIDX@#@COLOR@:@RRDPARAM@ GPRINT:p at RRDIDX@:AVERAGE: \: %5.1lf%s (avg)

What needs to be done to change the existing graphs on the system to display *LAST* instead?

Thanks, James