Total for Maximum Values

[Ceoltoir]

Hey all,
It might be a bit complicated to explain what I'm trying to do, but here goes:
I have a graph that I have created that has a total of 7 data sources, soon to be 13 once we have our additional links up. Now, I have written a cdef that totals all of those data sources (separate incoming and out going) and turns those values into bits, so that I can print a "Total In" and a "Total Out" for all of the sources. However, that works great for the "last" values of each of course by choosing "last" as my CF for the gprint... but now I'm trying to do the same thing, but for the "max" values of each data source. Choosing "max" as the CF simply prints the maximum total of the "last" values, but what I am seeking is simply a total of each "max" value for each data source. Is there a way to do this? Does this make sense at all? Am I going about the whole thing stupidly from the beginning?
I apologize, also, if this question has been addressed in the past; please post a link to that thread if it has.
Thanks,
Sarah