It comes from inflation that is being applied to HBD.

why not 30 % or 40% ?

That is what the consensus on the Witnesses came in at. They could have set it higher (still can) if the all agree.

For now, I believe the idea is to put it at the upper range of the stablecoin ROI market. We have the increase in haircut with the next hard fork which might help also.

I hope the next increase is tied to some time locked vault system. Maybe 1 year for 25% or 30% return.

Posted Using LeoFinance ^Beta