We are currently at extremes never reached before. We should expect regression towards the mean or for the pendulum to swing back past the mean. We should not expect to stay at the current extreme levels for low interest rates or for high monetary base to NGDP ratio for a long time.
So how do we return to normal levels? With US deficit spending levels, and Yellen as Fed Chair, I don't think there is any real chance of reducing the monetary base. Over a long enough time, the real GNP might grow by a factor of 2 and bring us back to normal levels of monetary base to NGDP, but I don't think we have that much time before something happens. So what will happen? The easy way is for prices to go up so that NGDP goes up. That is what I expect. Prices going up.
Prices going up by a factor of 2 or 3 gets us near the mean for the above data. However, after such extremes, I think we should expect a pendulum swinging to extremes at the other end of the graph. So prices should go up well over a factor of 3 and we should have high interest rates.