Date for 25 BTC per Block

[Stephen Gornick]

The moves in the chart over the past days don't appear they can easily be explained as variance.  

Previously Bitcoin hadn't seen the situation where the exchange rate was stable but the but mining difficulty swung one way or another to this degree -- and not like this -- huge dip followed immediately by a huge spike.  Something's coming down the pike.

FPGAs are attractive due to lower power required -- the megahash/Joule (Mhash/J) is an order of magnitude greater than that with ATI GPUs:
 - https://en.bitcoin.it/wiki/Mining_hardware_comparison#FPGA_Devices

Maybe production of FPGAs is going to start having a significant impact on the difficulty?

That would push the date to occcur earlier than December 9th.



 - http://bitcoin.sipa.be/growth-10k.png

[Remember remember the 5th of November]

40515 blocks to go at 6 block per hour makes it 281.4 days, so on 21st of december 2012.

Fix'd that for you.

[kjj]

The moves in the chart over the past days don't appear they can easily be explained as variance.  

Previously Bitcoin hadn't seen the situation where the exchange rate was stable but the but mining difficulty swung one way or another to this degree -- and not like this -- huge dip followed immediately by a huge spike.  Something's coming down the pike.

FPGAs are attractive due to lower power required -- the megahash/Joule (Mhash/J) is an order of magnitude greater than that with ATI GPUs:
 - https://en.bitcoin.it/wiki/Mining_hardware_comparison#FPGA_Devices

Maybe production of FPGAs is going to start having a significant impact on the difficulty?

That would push the date to occcur earlier than December 9th.



 - http://bitcoin.sipa.be/growth-10k.png

The red line and the green line are noise.  Even the blue line is sketchy.

[Sannyasi]

blocks produce at the same rate with difficulty adjustments. It will vary a little because of the lag behind each adjustment so it will vary a little bit but probably not alot. The mayans did get it right....... lord help us all......

wonders wth people did not look at this before posting rants.

I guess ignorance has it's place.......

[Stephen Gornick]

Just an update:

The hash rate increased 8.56% this last block adjustment period, which took 12.9 days instead of the targeted 14 days.
 - http://bit.ly/vFZwdF

That pulls the date earlier.

The last block on March 31st was 173,804.  So to get to 210,000 means there are 36,196 blocks remaining.  At 144 blocks/day (based on impossible situation of hash rate not rising or dropping) there are 251.36 days remaning until the block reward adjustment occurs.

That puts the date sometime on December 7th, 2012.
At this point, those betting on it being December 9th or earlier are on the winning side.  The wagers are 4X more for that than for the "later than December 9th" side:
 - http://betsofbitco.in/item?id=312

From the November BTC/USD low of $2.20 the current exchange rate at $4.85 is up 108%.  From the November difficulty low of 1,090,715 the current difficulty at 1,626,553 is up 49%.  So I suppose the difficulty still has room to rise or the price has room to drop because early estimates already just a few days into this next adjustment period show even further capacity has come online.
 - http://bitcoin.sipa.be/speed-lin-10k.png

It's still early enough that we could still see a November date, but I think the chances of a January 2013 date have now been completely eliminated barring a catastrophe.

[molecular]

thank you for this awesome update, Mr. Gornick.

I hope the date will be "pulled" even further to an earlier date by rising adoption / exchange rate / mining activity throughout the year

[Stephen Gornick]

I hope the date will be "pulled" even further to an earlier date by [rising difficulty]

Expect it:
 - https://bitcoin.org.uk/forums/topic/486-announcement-a-public-company-is-being-formed-to-enter-asic-bitcoin-mining-marketplace/

[Xmufa23X]

December 21st. Just for shits and giggles.

[dooglus]

Here are a couple of stupid plots of block chain length against time.

This one clearly shows we're on target for a late November reward halving:


And this one shows it's definitely late December:


Hope that helps!

[molecular]

I hope the date will be "pulled" even further to an earlier date by [rising difficulty]

Expect it:
 - https://bitcoin.org.uk/forums/topic/486-announcement-a-public-company-is-being-formed-to-enter-asic-bitcoin-mining-marketplace/

I doubt Vladimir will be able to have operational mining capacity early enough for this to be relevant here.

[Serenata]

I too want date for 25 btc

Heh.  When I first read this, I thought that you were very lonely, if you were willing to pay 25 BTC for a date.  I didn't grok your question until I read the next reply.

looool
Just couldn't help myself....

[Stephen Gornick]

That puts the date sometime on December 7th, 2012.
At this point, those betting on it being December 9th or earlier are on the winning side.  The wagers are 4X more for that than for the "later than December 9th" side:
 - http://betsofbitco.in/item?id=312

It could end up being a photo finish!  This last adjustment period id is looking like we'll end up with a 3% drop in difficulty.  Some explanation for that drop might have to do with the mining on blocks that became orphaned, thanks to miners that hadn't upgraded to code that supported changes to the Bitcoin protocol.

That puts the date late December 8th, 2012.  The bet says December 9th or later so there is still more than 24 hours cushion for the "December 9th or earlier" side of the bet (the "agree").  But a lot can happen yet.  With 22% margin, either the price needs to go up or there will be more GPU miners droppng out.
 - http://bit.ly/HEzoMm  (mining profitability currently 22%)

[molecular]

That puts the date sometime on December 7th, 2012.
At this point, those betting on it being December 9th or earlier are on the winning side.  The wagers are 4X more for that than for the "later than December 9th" side:
 - http://betsofbitco.in/item?id=312

It could end up being a photo finish!  This last adjustment period id is looking like we'll end up with a 3% drop in difficulty.  Some that had to do with the mining on blocks that became orphaned, thanks to miners that hadn't upgraded to code that supported changes to the Bitcoin protocol.

That puts the date late December 8th, 2012.  The bet says December 9th or later so there is still more than 24 hours cushion for the "December 9th or earlier" side of the bet (the "agree").  But a lot can happen yet.  With 22% margin, either the price needs to go up or there will be more GPU miners droppng out.
 - http://bit.ly/HEzoMm  (minng profitability currently 22%)

If, due to exceptional circumstances, we end up with a diff drop of 3% that doesn't reflect a drop hashrate, then that difficutly was measured "wrongly" and we're hashing blocks faster than 1 block per 10 minutes in the coming period, which will effectively move the date closer, no?

[Stephen Gornick]

If, due to exceptional circumstances, we end up with a diff drop of 3% that doesn't reflect a drop hashrate, then that difficutly was measured "wrongly" and we're hashing blocks faster than 1 block per 10 minutes in the coming period, which will effectively move the date closer, no?

Yup, but for some reason that hashing in the last couple days hasn't been rebounding to those previous levels.  So there probably are other contributing factors.  There has been some selling of hardware as some miners unload GPUs and buy FPGAs (here's one example, by the person who held at one time the record for "fastest rig" https://bitcointalk.org/index.php?topic=75616.0 ).
 - http://bitcoin.sipa.be/speed-lin-2k.png

So if those GPUs get sold to others who will be mining, that hashing will not just return but will be in addition to the new FPGA hashing purchased using the proceeds from the GPU sales.

But with a sub-$5 BTC/USD and this difficulty level, those with GPUs and are paying $0.15 or more per kWh are just barely breaking even.  Whether or not the new hashing from FPGAs more than compensates the lost hashing from those dropping out is the reason that bet could still go either way.

[Stephen Gornick]

It could end up being a photo finish!

It's turning into quite a contest!

Now, going forward if mining keeps the target 144 blocks per day from here (yes, a big stretch but on average ... 144) the date for block 210,000 has moved later and now sits about noon on December 9th, 2012.  It was targeted at December 7th, at one point.

 - http://betsofbitco.in/item?id=312
 - http://bitcoin.sipa.be/speed-lin-10k.png

[steelhouse]

BTC - 10 minute blocks, retarget every 2016 blocks, 2 weeks               
1/3/12   160370   8018500   33%   50   7200
12/13/2012   210050   10500000   13%   25   3600
12/13/2016   420434   15750000   4%   12.5   1800
12/13/2020   630818   15960012.5   2%   6.25   900

I did the calculation 1/3.  Annual inflation rate will drop to 13%.

[Stephen Gornick]

I did the calculation 1/3.  Annual inflation rate will drop to 13%.

Right now it is at 29.5% annual (dropped below 30% threshold earlier this month).  Hadn't looked at it recently.

[Fuzzy]

Once the BFL Mini-Rigs start hitting the street at 25GH each, you can bet your bits the difficulty will rocket.

Imagine, the Network total is ~11 THs, each miniRig runs 0.025, so for every 40 rigs turned on an extra TeraHash is added to the network.

This is going to be very interesting, and very bad for anyone still mining on video cards (me).

EDIT: as pointed out, 25GH is 0.025TH, not 0.25TH

Apparently 3 pm is too early for me to do maths

[Technomage]

Once the BFL Mini-Rigs start hitting the street at 25GH each, you can bet your bits the difficulty will rocket.

Imagine, the Network total is ~11 THs, each miniRig runs 0.25, so for every 4 rigs turned on an extra TeraHash is added to the network.

I believe your math is off here. If a "mini-rig" is 25 GH, then it takes 40 of them to get 1 TH.

[kronosvl]

Once the BFL Mini-Rigs start hitting the street at 25GH each, you can bet your bits the difficulty will rocket.

Imagine, the Network total is ~11 THs, each miniRig runs 0.25, so for every 4 rigs turned on an extra TeraHash is added to the network.

This is going to be very interesting, and very bad for anyone still mining on video cards (me).

25GH=0.025 TH or 40 miniRigs for 1 TH