Combining events into event keys and adding sums, respectively
I want to take this :
And make it so each eventtitle is paired with another eventtitle in a key pairing, for example Annual Meeting 2012-Annual Meeting 2013.
I want to do every combination of the event column with the other events (Annual Meeting 2012-Nurse Manager Fellow's; Annual Meeting 2012-From Worst to First... etc.) and I want to add up the sumregistration column for each event (so Annual Meeting 2012-Nurse Manager Fellow's sum(sumregistration) = 8300) if that makes sense.