Because the creation of STEEM is at such a high rate, I suggested here and on other threads that we should introduce a fee on rewards. A small percentage that is taken every time STEEM is created which can be recirculated within the economy. This reduces the amount of STEEM needing to be made as there's already a supply within the economy which can be used to pay rewards. If creation of rewards then become more frequent, and if there's less rewards being handed out, we create a surplus that can be paid back to investors. 

The same thing happens with banks and taxable incomes. State banks tax incomes to recirculate money, reducing inflation, and then use surplus for government spending. (As I understand)