February 5, 2014. Difficulty rose by +19.49% to 2.62B from 2.19B.
Change
+19.49%
New difficulty
2.62B
Period length
11.7 days
Network hashrate then (7-day)
0.0 EH/s
Bitcoin price then
$803
Hashprice then
$151,265/PH/day
The 2,016 blocks before it took 11.7 days instead of 14, so the network had more hashrate than the difficulty assumed, and difficulty rose by 19.49%: one of the largest adjustments on record. For every machine on the network that is a pay cut of the same size until the next retarget.