The spawn rates are also very high
during events that do not need Fangbeasts. I can't recall the event's name, but in it, we were required to chop Red Acer Trees to gather material. Fangbeasts were spawning with every three to five chops; I remember this well because I summoned every swear word I learned, and invented new ones too by the end of the event. And then, there came the Monster Hunt and the Fangbeasts went into hibernation
But I like your idea of charting this. Perhaps you could start a new thread on this and players could post and update their posts so all of us can keep track on our "luck."