Change units of y-axis in a TH2D histogram

I want to change the units of the y-axis of a TH2D histogram in the way of y = y*c where c is some constant. What is the easiest and cleanest way to do this?

Thank you! It worked great. Is there a reason why this is not a built-in function? It is very useful

Nobody cares.

I think @moneta can help.