Consider about essay's layout. I means put space between paragraph, it comforts reader to read your whole essay.
The graph illustrates the quantity
It is used for describing thing(s) not person
Maybe the example from my dictionary will help you
He had consumed a large quantity of alcoholThe police also found a quantity ofammunition in the flat.After that the proportions of USA and Sweden increased to a peak in 1980, where USA represented 15% while Sweden was also managed to come near to that point.
Be careful with your observation, I think three of trends depict their peak in 2040 and it predicts will increase in following years.
However the chart also predicts the proportions in 2040 which are contradictory tothe past .
please be specific when the main years you means ?