I would rework it with a lower return 6~7%. I haven't seen 12% consistently.
Also, the first column could be years to retirement countdown. Ie. 40, 35, .... 10, 5. That would be more useful for Mustacians.
Oh and instead of 1M it could be tailored to what you think you need to be FI.
Oh, oh, you could start with a present value greater than zero.
It looks like I could have some fun with excel.