In a research note on Sunday, Jefferies said bitcoin mining profitability fell in September from the previous month as the average price of bitcoin remained largely unchanged while the network hash rate rose by about 1.7%. The investment bank noted that average daily revenue per exahash fell 2.6% from the previous month. Analysts Jonathan Petersen and Joe Dickstein wrote: "It now looks like October will be a tougher month, as the price of BTC has only increased by around 5%, while the network hash rate has increased by + 11%, which is more than enough to offset this increase."