It seems to me that there is less turbulence in the last 10-15 years. Does anyone know off hand whether this is the case?
Personally, I think it may have more to do with pilots more liberally adjusting course to avoid turbulence. High-profile incidents related to turbulence, newer tech, and the padding of flight schedules to game on-time metrics would make it an easier decision for a pilot to avoid turbulence.