You have to remember that back in 2011 everybody was saying "Sure the price has been dropping, but it could jump up again any moment now!" What happens is that as the price rises people see difficulty is not as high as the price, making mining profitable, so they start building a mining rig. That takes time, and there will be people who do not get their mining going until after the price has peaked. But they do not want to have wasted all that energy they spent building this thing, so they start running it anyway. Also, when the price drops, people who are already mining have already done the hard work of getting the thing set up, so they keep on mining and hoping the price will go back up again; if they are still marginally profitable they will keep mining but not add any more capacity.
The other thing to consider is that technology has been improving, and so as more efficient ways of mining come to market the total hash rate will increase even if the price remains constant.
Yes, and these are the dynamics i came up with to justify the difficulty graph.
But i cannot understand the 2 month delay in peak of hashpower compared to price.
In those days i think most people mined on GPUs.
2 months is way too long to order and build a couple of pc's with GPU's.
It takes me maybe an hour to get from pc components to a ready to use computer. That includes OS and drivers and all that. Ordering components doesn't take 2 months either.
So at the very least one would expect that there would have been a strong negative effect on the difficulty just past the price peak. People investing in mining rigs could have simply canceled their orders.
I can remember that right after the price peak there were a lot of people forced to sell their rig because price expectations were not met. There was a sell off of sorts. I cannot find that back in the data. It looks as if the miners are completely oblivious to
current price and always react to
past price with a more or less fixed latency. Somehow the information about past price tunneled its way into the future without being affected by months of negative change just to have a singular effect on capacity in the future. How did this information of past price survive so far into the future?
The timescale of the data suggests that miners must have been ordering en masse
after the price peak, while the price was going down.
For me this is a strong indication that the difficulty data is delayed somehow and the actual reaction of miners was much closer to the actual price, possibly even preceding it.
The data does not make any sense to me otherwise. Miners do not live in a universe where they only see an old price and are only capable of reacting months afterwards. Most of them are capable of reacting within a week to market changes but somehow they were incredibly blind and completely irrational when looking only at the price changes.
Another thing that bugs me is that the data is so smooth. I'm pretty sure hat hashrate in those days was much more erratic. There were tests with clusters and stuff like that. None of those show up on in the hashrate data. This suggests that the available data is already averaged (also implying a latency).
As i said above, i needed to take a 100 day running average to get from price to difficulty. 100 days is a loooong time. I see no reason for the network to have such a strong lingering memory of a sentiment from 3 months back.
So while i'm tempted to see the simple side of things there are still some details that don't make sense at all to me. I cannot find a justification for the way difficulty repeats movements with such a high latency and smoothness.