About 40 TeraHash will make 1 btc a day.
I am not seeing this at all. Is there a chance you missed a zero? Looks to me like
4TH (not 40) produces 0.01126 BTC/day. That suggests that
40TH would be much closer to .1 BTC/day.
I am just using bitcoinwisdom as my simple calculator for this. It also fits with experience with my 3.4TH Avalon 6. That doesn't get anywhere near .1 BTC/day.
I think the more accurate answer is about
400 TH.
It is much closer to the 400TH, it's around 365 TH to get 1.02745126. And that does not include electricity cost... so to pay electricity 400+ is a pretty fair guess. People have to remember value is around 461 currently so 365 a year is a little over 168K.
It's pretty unrealistic for most to mine a 6 figure income. Just is a lot of initial investment, I'm sure there are some that do it. But it will be few compared to overall amount of miners.