Page 1 literally says it is: "Coinbase (block reward): 10 000 SMLY (halved after 7 years) goes to miners (10%), dividends (45%) and donations (45%)"
Only 10% for miners is incredibly discouraging.

Ah, yes, sorry, I've changed this to just say
coinbase since it now confused me as well.
Usually we think of
coinbase=block reward = miner's reward for a coin and this is not the case for SmileyCoin.