Yes, I also would like to know.
Whenever I get to my journeys end, I get a full row of green “trees”, with other green light below.
I think that you get a “starter for ten”, with one tree illuminated, if you are in ECO mode.
I drive gently most of the time, and always avoid using my brakes to slow down, which I know helps with the economy, pulling it into B , and then touching the big pedal at the end. The downside of this, is disc rust!
Great car!