How is the intensity of artillery in Ukraine compared to previous wars?

How many artillery rounds are used per area and time? How does that compare to different fronts and phases of the world wars, Korea or Vietnam?

Are they firering that many for the same reasons compared to history or for different reasons? E.g. is it because of lack of production, lack of targets or supply line problems?

How effective is the artillery in shells per casualties inflicted compared to before? I guess territory taken per shell is rivalling WW1 western front.