Thanks for the info. I didn't know that. So the Dec 26 quake was the third greatest quake ever scientifically recorded? All three quakes you mentioned happened in a 45 years time span, which is a fraction of geologic time.
Yes, the Sumatra quake was the third largest quake of the last 105 years.
However we really only have actual quake measurements for about 100 years and really accurate ones for perhaps 30-40 years.
Actually, of the 12 largest quakes since 1900, SEVEN of them occured in a 15 year period from 1950 to 1965. There's interesting debate over whether that is random or not.