Yes, I too was confused by the 0% APR in the wallet, while in posts people was talking all kinds of different rates. That was the main reason is decided to dig into this myself. BTW, the wallet is correct about the APR on SBD and STEEM in you savings, but it does not say anything abou the SP rate.
Like I mentioned to you in the first reply, I was going to look into a possible mistake I made. Here's a link to what I did:
STEEM #1 Dilution of STEEM & How to Break Even (INTEREST RATE CORRECTION)