Long tem cost of right to coin

I get a half point per year out 30 years from now.  I base this on a wild guess that market risk carried by the Fed be a half point.  It is fake to project to an infinity, hence we get residual cost, the right is still there, we have just bounded the known unknown in cash accounting. We get a monopoly insurance fee, positive, and were happy for it. We don't get there until the third contract, we still have to roll the dice.