Bitcoin (Cash) historic and forecasted drift

These graphs show Bitcoin's and Bitcoin Cash's systematic deviation from the (purely) theoretical schedule of 10-minute blocks since genesis. They are similar to Jonathan Toomim's graph, but also shows the underlying mechanisms, and includes future drift induced by future hashrate increases. This drift estimation is based on Bitcoin's drift between 13 November 2017 and now, ASERT's drift being about 4.26× times smaller (assuming Bitcoin Cash and Bitcoin experience similar hashrate growth going forward), and the fact that Grasberg uses a variant of ASERT to target 11.25 minute block times until historic drift is corrected. As an indication of uncertainty, all graphs include an error bandwidth based on scenarios with ±75% drift. The uncertainty in block height translates into a much smaller uncertainty in coin supply, because every halving halves the sensitivity of supply to block height. Bitcoin Cash with ASERT and Bitcoin result in a nearly identical and well-predictable supply schedule for the future, while Bitcoin Cash with Grasberg suddenly takes a different turn.

As to whether that sudden monetary policy change is a good idea, I'll refer to noise's great article.