![](https://ip.bitcointalk.org/?u=http%3A%2F%2Fhashingit.com%2Fimages%2Farticles%2F20140524%2Fsimulation.png&t=627&c=QN1xdIx0yO9zFw)
There are more thoughts at http://hashingit.com/17-reach-for-the-ear-defenders
The 18.1% difficulty increase may well just be another example of noise in the difficulty, but equally well the slighly lower numbers for the previous 3 changes may have been noise too
![Undecided](https://bitcointalk.org/Smileys/default/undecided.gif)
{edit 2014-05-24} I don't mean that the whole 18.1% is noise, but it's quite possible that the real increase in hashing rate was as low as 12.5%. It's also possible it was as high as 24%, but given the trend over the last 4 months it seems more likely that the 18.1% was high, just as the previous 10.66% was probably low.