I just don't understand why people with the same hash pawer don't have the same stats. For example, i'm running since december my rigs 24/24 and i should have same stats like the one on the main page with a different ratio.

This night people had a lot of unexchanged but not for my 5 rigs that have around 8mhs. I'm on amsterdam server, rejected are around 2 or 3% in cgminer, same for stale. Good ping to amsterdam and eu server around 50ms.
My unexchanged were very flat and my payout is around 0.01btc/mhs/day. Compared to the main graph that has around 0.02, there is something wrong.

I suspect the server location to have different earnings. I hope i'm wrong.