May 25, 2013. Difficulty rose by +8.64% to 12.15M from 11.19M.
Change
+8.64%
New difficulty
12.15M
Period length
12.9 days
Network hashrate then (7-day)
0.0 EH/s
Bitcoin price then
$133
Hashprice then
$4,551,157/PH/day
The 2,016 blocks before it took 12.9 days instead of 14, so the network had more hashrate than the difficulty assumed, and difficulty rose by 8.64%: a large adjustment. For every machine on the network that is a pay cut of the same size until the next retarget.