With Hive, curation lies between 10 and 18% according to how well it's done.
Considering that only a part of the token holders actually curate and create posts, I think that the inflation is somewhat lower. On the other hand there is also a part from the inflation that is burned through the proceeds from the ads on the platform. Another component is the number of people that join the platform and increase the demand for the token. It's actually quite a complex economy already :-)
!ENGAGE 20