When I received my obligations, which are: no colors, no numbers, no grafic elements but use frame, I started to think about my new project:
I choose to use glasses for main elements because the glass is transparent and has no color. In this way I keep my obligations not to use colors and grafic elements.
I arrange them 
on a black plate 
with a rectangle form and in this way I had a frame. I chose glass with different forms and heights and in this way I reproduce the main purpose of the project to visualize different percentages without using numbers.