Kirk here. Everyone in Kumamoto knows that we have been having lots of aftershocks. This graph helps put that experience in perspective. It shows we have now had 165 quakes of over magnitude 3.5, more than the other earthquake disasters shown on the graph. They are as follows:
2004, Niigata 2008, Iwate and Miyagi 1995, Hanshin (Hyogo Prefecture) 2005, Offshore Fukuoka
I don’t see anything about the 2011 disaster that caused the nuclear meltdowns, so assume that there were more quakes in that case.
This graph is taken from an article in the Asahi Shimbun: