There are several reasons for this:
1. Prices go up and we don’t always change the RPP immediately.
2. Exchange rate varies so although we fix an RRP for each currency the actual amount we get varies according to the exchange rate.
3. Our printer sometimes reduces prices.
4. There is a variance in wireless costs when sending e-books.
5. We have to allow retailer 35% discount and 40% in the US. When we sell directly with a shop we have to pay shipping. When books go through our distributor we don’t.
6. The biggest profits are made on large orders from authors.
7. Prices have to be neat – so there isn’t a set percentage profit.
8. Shipping rates can vary. Sometimes they are reduced if our printer is sending other books to the same outlet.