Tambora was in 1815
Krakatoa was in 1883
So on average we have some time before the smaller ones go off.
Judging by the averages—we may be due for one of the bigger ones. Not sure. How do you figure?
Generally..one to 3 vei 6s goes off every century. VEI 7s about one or two every 200 years.
8s? years and years.
But, those averages are not really consistent, two or more could go off one after the other-its up to mother nature.
BTW..as yo most likely know.
Tambora was a VEI 7.
Krakatoa was a 6-estimate.
Novarupta was a 6
Pinatubo was a 6.
It isnt really the size sometimes...its the duration more than the size.
There was one that went off at Iceland that killed more people than could be imagined. It was a 4 or 5. But it went on and on and on and on. Pumped massive amounts of gas into the air.
I will let someone else research that one.