In most skills you get faster at a thing the higher your level is. Like cutting yew trees. Is it depentand on you level or your exp. Like when you just get 98 is the same cutting rate as one exp point away form 99. Or does anybody really even know.

It only depends on your level. XP are only there for seeing how close you are to the next level.

i am almost sure its based on lvls, because with str for example, you won't hit higher until you hit a certain level.