If you're trying to predict RAC have a look at the gridcoin mining experiment. I have been running for many months. It's much more complex than it looks at first sight. Following the reasoning in this article would mean one of the early exponential curves (estimations). It didn't really follow that at all.

I have seen many of these 'predictions'. The thing is nobody really keeps track of the RAC to match those predictions. At this point in time something very interesting is happening. At least, I think, I will post about it shortly.