Hi Albert,
There's a couple of different price points that give different royalty values. I chose a cheap price point that comes with 30% royalties but if you choose a higher one you can get 70%. I reckoned that I'd struggle to sell any at the higher price point and I just wanted to get the book out there.
The thing I didn't know is that you have to accumulate 100 worth of royalties in a currency before they pay it out, so I doubt I'll be seeing any cash any time soon. It's really gratifying though whenever I see that someone has bought one (they do a little chart where you can see your sales volumes - my sales axis goes no higher than 8 at the mo!), even if I know most of the purchases are by friends.