``Rated Current 108A``
Why is it 108A and not 10.8A? I don't understand that at all. I see that bitmain also doesn't use the decimal:

And it's true about the subsidy payout halving from 25 to 12.5 BTC per block (though I am not sure of the exact date). It does this every 4 years by design. That will be an instant 50% reduction in mining profits from that moment forward. I am not sure how many of the mining estimate calculator sites take this into consideration as of yet. One thing they do NOT include, but which is becoming more and more important as time goes on, is...the fees collected from all the transactions. Those fees don't disappear into the void. They don't go to the person who invented the system either. They go, instead, to the miners who solve the block (in addition to the subsidy). They can't be calculated ahead of time, because they depend entirely on how much in fees was collected in that block.
You can infer from the slope changes in this curve that the payout halves. As time goes on, a larger and larger portion of the overall payout to miners will be the fees collected rather than the subsidy which keeps halving every 4 years.
