Add comment/subtitle to a graph

Hi,

I am trying to add a comment or subtitle to a graph.

What I am trying to do is to plot a histogram with the assets weights of a portolio.

Below this graph, I want to add a small text or table with the risk and return of this portfolio calling a variable (I want to do this for many portfolios so I don't want to write each time the risk and return, I want to call a variable to display it)

Thks!