Certainly 3 variables is common place? https://i0.wp.com/flowingdata.com/wp-content/uploads/2018/08/fake-YouTube-views.png https://i0.wp.com/flowingdata.com/wp-

Certainly 3 variables is common place? https://i0.wp.com/flowingdata.com/wp-content/uploads/2018/08/fake-YouTube-views.png https://i0.wp.com/flowingdata.com/wp-content/uploads/2018/08... 4 is pretty common too, but I agree that 4-5 is tricker to make sense of.