EPC is Los Pollos is defined quite differently.
In Los Pollos, each click is defined as sign-up (based on my testings). For most offers, Conversion occurs after inserting the Credit Card information.
With that said, when EPC is $0.0375, it means, on average, you have earned $0.0375 per click. So you might have 10000 unique visitors, about 700 registers, and only 3 convert.
The EPC will be calculated by dividing total earnings from the 3 conversions with 700.
The following is a screenshot from my account:
I spend ~$40 and gained back ~$25 (~$15 loss). I used popunder ads, but as you can see, the effectiveness dropped heavily on the second day. In short, as the traffic pool is limited (at least in the network I'm buying from), the same user might see the ads more than once; thus, reducing the chances of conversion.