20% interests per annum is not equivalent to 316 coins in 16 or 17 days (I assumed daily compounding of interests).
You're assuming everyone is staking.
Bittrex holds ~47% of all coins and most of their wallet addresses seem to be flagged as belonging to them. I don't think I've ever seen one of those flagged addresses staking.
How is the number of coins that are generated (by staking) in each block calculated? How does the formula look like?
Why don't you ask every other PoS coin in existence how theirs is calculated.
You are obviously not interested in supporting this coin, so why not ask those you are supporting how theirs work.