I also found that the bubbles (or peaks, if you would prefer to call them that) seem to occur approximately every 234 days (an observation already mentioned on this forum) - with the minimum time between peaks being 213 days and the maximum time being 235 days. Considering there have been six peaks, that is a very small degree of variability for such a notoriously volatile phenomenon as Bitcoin.
Could you please post the dates of the peaks and how exactly you define a peak?
By my count, there have been six peaks as well. However, the number of days between peaks that I've identified has ranged from 99 (2010-11-07 to 2011-02-14) all the way to 664 (2011-06-09 to 2013-04-09).
PS. Cool graph. How did you generate it?