Dynamic Volume/area or funnel visualization

[Leon Rosen]

Good Morning!

For several years I've attempted to find a way to accurately visualize population sizes of customers within a marketing funnel in a 2D environment.  

My current process is to set the diameter of a level within a funnel based off of the area that that circle slice would equate to.  Then using a relative ratio, setting each level based off of the area/audience size and respective diameter of that circle/level.

Does anyone here know of a solution in GoogleVis? or another tool?

Thanks

Leon