Maybe I'm being stupid again, but...

I can see the 3-month EPCs for my advertisers under their "details". But how do I get MY 3-month EPC for THAT advertiser, calculated across the same timeframe as used in the merchant EPC calculation?

I can get my EPC for a merchant for today, yesterday, this month, last month etc., but not, it seems, for that "three month period beginning five months ago" timeframe...?

is there a quick method I've missed, or do I have to work it out by hand?

I want to have an exact comparison so I see how I shape up with regard to their average, and how much leverage I thus have in asking for a higher commission %.