Sorry didn't realise it was paywalled. This is it minus a few charts (1yr price, difficulty, miner revenue):
If Bitcoin is a bubble, it is a bubble that began deflating on November 29 2013. At its proudest moment the price of one unit of the much-ballyhooed virtual currency was $1,242, which meant the value of all the Bitcoins in the world was just under $14bn.
These days it trades mostly in a range of $450-$650 a coin and at a market cap of $6.5bn. The jury is still out on whether the Bitcoin technology will prove robust and the currency itself will find mainstream use. If the answer to either question is no, then no amount of hot air is likely to keep the price at current levels.
But even as the Bitcoin price decays, there is another candidate for the bubble label: the market for the specially designed computers that hold the Bitcoin network together and “mine” for newly minted coins.
Nicolas Courtois, a senior cryptography lecturer at University College London, has calculated that at least $1bn has been invested in this “mining equipment”, and some miners, who wish not to be identified, suggest that could be a modest estimate.
Prices for the latest computer hardware have been chased higher because investors have required faster and faster machines to make narrower and narrower profits mining for Bitcoin.
Mr Courtois estimates a majority of investors are making a loss.
“It has been a very bad experience for most investors and a jackpot for a few lucky ones,” he says. “The bottom line is that the production of mining machines was much higher than expected and advertised.”
Bitcoin price
Miners are central to the operation of the virtual currency. Linked together, they are the peer-to-peer network that confirms transactions and maintains the online ledger showing where all the Bitcoins are. New coins are their reward for taking part, but the likelihood of getting a coin has decreased as more miners come online and the number of Bitcoins approaches the maximum allowed.
When the pseudonymous Satoshi Nakomoto created the virtual currency in 2009, he envisioned a decentralised market powered by ordinary users operating equipment no more sophisticated than a MacBook. But now development costs for the most cutting-edge technology, in US dollar terms, can run into the double-digit millions. The biggest miners now run large rigs, sometimes filling entire warehouses, with giant fans to keep them cool.
Bitcoin mining difficulty
Bitcoin folklore has it that a savvy German miner known as ArtForz worked out how to adapt graphics processors (GPUs), the sort found in video game technology, to run the Bitcoin algorithm much more efficiently in 2010, sparking today’s arms race. The era of Bitcoin mining farms chock full of precariously placed cables and energy-intensive overheating processors – evocative of Star Trek’s Borg villains – had begun.
“We’ve paid between $10m and $15m for the development of our 20 nanometre technology, depending on what you include in those costs,” says Nanok Bie, director of marketing at KnCMiner, a Sweden-based miner that develops rigs for commercial distribution.
Bitcoin miners' revenue
The 20 nanometres refers to the size of the microchip that makes the cryptographical computations needed to process Bitcoin transactions and hunt for new coins.
Once the preserve of libertarians and technowonks, Bitcoin began attracting more attention last year, when the price of a single coin climbed in fits and starts from just $14 at the beginning of January 2013. Believers argued it could replace what they claim are devaluation-prone fiat currencies, or undercut traditional payments processors such as Visa and MasterCard or banks.
In recent weeks, the price has again been volatile. An increasing number of companies have won headlines by announcing they will accept Bitcoin as payment for online transactions, but these firms typically cash in their Bitcoin for dollars or other currencies immediately on receipt. This has created the situation where increased adoption of the currency can depress, rather than increase, the price.
The price weakness further narrows the margins on Bitcoin mining, spurring ever greater desperation to obtain the latest equipment. Buyers of mining computers report having to pay in advance for machines that take months to arrive, and internet discussion boards are full of accusations of unscrupulous sellers delaying delivery so they can use machines for themselves, or failing to deliver what they promise at all.
In depth
Bitcoin
Bitcoin
As interest in Bitcoin increases, US officials are looking into how to regulate, rather than shut down, the virtual currency
Firms such as KnCMiner and rivals Butterfly Labs and Cointerra are among those hoping to expand sales beyond Bitcoin adherents to investors who believe alternative virtual currencies, such as Dogecoin or Litecoin or other Bitcoin copycats, might break through to the mainstream as well.
These manufacturers are hopeful that all the investment in their industry will spur innovation. As well as ultra-fast, ultra-efficient chips, future technological developments could include mining rigs whose excess heat is channelled to heat homes, or investments in low-cost energy production such as solar power, says Mr Bie.
For now, says Mr Courtois, a number of players are willing to mine Bitcoin at a loss, either in the hope of a long-term turnround, or to support the system, or to get hold of a currency that is anonymous and untraceable and therefore useful in illicit transactions.
Economics, however, may well catch up with the whole system. The fate of Bitcoin and its miners are tied together, and the outcome will decide whether the whole virtual currency experiment is ultimately labelled a bubble.