Basically, this cycle always repeated again and again in every year along bitcoin journey. I don't think this chart represent bitcoin development - movement over time as in the beginning and midway, bitcoin charts fluctuate a lot but seems increase rather than significant decrease because of fear, capitulation or back to the mean, and in the end bitcoin price should be steady when it reach the highest peak.

But, if we talking about bitcoin bubble, we're still on awareness phase as most people in the world don't know about bitcoin or just know that there is a digital currency named bitcoin, but don't really know what bitcoin is. Wait until all media write about bitcoin and cause more people aware of bitcoin existence and its usability.