I don't know if this question is a hoax but here goes... The amount of the drop from 4500 to 2800 is 1700. The percentage of the drop is 1700 / 4500 = 0.377 ad infinitum (to infinity) or 37.77~ percent. So when you subtract 37.77~% from 4800 you get 2800. Therefore 2800 is a 37.77~% decrease from 4500.
