In a previous post, we discussed bitcoin miners’ incentives to undertake a 51 percent attack given the current condition of the bitcoin market. We also speculated that high profits and free entry would cause more miners to enter the market, driving marginal mining profits to zero in the long run. Since then, the price of a bitcoin has declined over 40 percent and both the hash rate and the difficulty level of the bitcoin mining problem, which adjusts automatically to changes in the hash rate, appear to have leveled off. Our most recent calculations suggest the long run may have arrived.

In June 2014, the mining pool Ghash.IO briefly controlled more than half of all mining power in the Bitcoin network, awakening fears that it might attempt to manipulate the blockchain, the public record of all Bitcoin transactions. Alarming headlines splattered the blogosphere. But should members of the Bitcoin community be worried? 

The Fedwire^® Funds Service is a large-value payment system, operated by the Federal Reserve Bank of New York, that facilitates more than $3 trillion a day in payments. Turnover in Fedwire Funds, the value of payments made for every dollar of liquidity provided, has dropped nearly 75 percent since the crisis. Should we be concerned? In this post,…