https://bitcointalk.org/index.php?topic=521520.msg9849837#msg9849837

Raskul wrote a tutorial here:
https://bitcointalk.org/index.php?topic=894826.msg9849580#msg9849580

Edgar,
You don't follow our thread closely enough ...

Edit: In the first few days, the return was 30X over BTC, afterwards 9X and it settled at about 3X up until the end of the POW period