That said, your numbers dont quite add up either. At todays difficulty, which has been in effect since the end of last dividend, 1150TH will yield ~300 BTC per week, minus 73 hosting is ~227 BTC for this friday. Next difficulty is projected to be 17B which would result in ~238-73=~166 BTC. Okay probably a little more next week, since a few days will be mined with todays difficulty, but the week after that it will be in full effect, and difficulty might have gotten another increase.
Maybe I'm wrong about this, but... the difficulty level tells how hard it is to find a block; from this we can also calculate expected interval between finding blocks. But this assumes that the network hashrate remains constant since the last difficulty adjustment. In reality, the expected mining returns would trend more closely with network hashrate, especially if the hashrate increases significantly.
Correct?