Is average block time presented at
http://stats.expanse.tech/ an average of the last XXX blocks? Or is it an average of all blocks found including the ones at low difficulty when Expanse launched?
Yup It is including the launch before difficulty stabilized. Some of it is from blocks coming in quicker after the launch too, from the ever-increasing hash rate as more and more people got interested and starting mining.
Let me explain: You can think of this as a kind of growing pain -- getting too big for your clothes too fast.
When hashrate increases by ALOT very fast, ESPECIALLY like it did at launch, but also after the launch there were a few times where alot of new miners got on board over a few hour period. All of that isn't suddenly pointed at EXP in the blink of an eye over one block; It is a gradual increased over a few hours. The difficulty increases as more hash gets added, but because more people are joining in following that, there ends up being slightly more hashrate then the difficulty was calculated for. The result is a slight increase in blocks solved compared to the expected until the hashrate is no longer increasing (like now, it is pretty stable).
When Hashrate pulls away from the coin, the inverse will happen -- difficulty will be up higher with less hash rate to solve it, result in slightly less blocks per hour. This is normal behavior and over a moderate time window averages evenly to the desired rate per hour.
Let me know if you need any further clarification or have any other questions. ;]
