Even if Black Arrow delivers in time,iits still 2 and a half months away.By that time bitcoin difficulty will increase so much that we wont earn coins anywhere close like we are calculating now.
wrong. black arrow is due in 60 -75 days 5 or 6 diff adjustments. do your math
at 30% you get this
908 mill now
1180 mill dec 22
1535 mill jan 4
1995 mill jan 16
2594 mill jan 28
3372 mill feb 9
4384 mill feb 21
[...]
Almost correct, but with a 30% increase in difficulty, the 2016 block period is shortened equally (to below 11 days; 14/1.3=10.77). Correct calculation for 30% difficulty increase:
date diff in mio. time frame for 2016 blocks
10 Dec 13 908 10,77
20 Dec 13 1.180 10,77
31 Dec 13 1.535 10,77
11 Jan 14 1.995 10,77
22 Jan 14 2.593 10,77
1 Feb 14 3.371 10,77
12 Feb 14 4.383 10,77
23 Feb 14 5.698 10,77
6 Mar 14 7.407 10,77
I expect the difficulty increase to slow down a bit. Currently there are roughly 6.5 PH/s running.
To boost that up to a difficulty of 7400 million until beginning of march, you need another 46 PH/s added to the Bitcoin network.
The total amount of PH/s (that is yet announced, but needs to be delivered) for 2014 is only a bit more than 20 PH/s.
Even with the late delivery that was announced for 2013 (and that may happen in early 2014) it can be doubted that the total network speed will reach more than 50 PH/s by beginning of march 2014.
But who knows...
The last retarget has come on Dec 21, not Dec 20, with nearly exact 30% increase (even slightly higher).. ;-)
But you're right, the time periods in the OP weren't correct either, they were even the same for different expected increase rates.