Well SAS lets do the math...
Before yesterday:
Osprey serious mishap rate - 1.28 per 100,000 flight hours
Marine air fleet serious mishap rate - 2.6 per 100,000 flight hours
Even if they were only at 100,000, if you include the incident yesterday that would put them at 2.28, which is still lower than the fleet.
(But of course, it looks like your numbers are trying to include accidents that happened before the V22 was out of the prototype/testing stage or even deployed.)