Blunion
I'll have to echo Jamie's post, the green line moved up and down for me last night in my race. The same was recorded by another manager in my race.
A driver of mine was in 2nd, and dropped to 3rd after a pit stop. The green line followed him there, and my objective was to finish 2nd or higher. I'm thinking there's a bug here.
This is my experience exactly. While racing it was constant, as per the screen shot. But when I pitted it would move.