yellow103

Doesn't say how much of this is due to new trees on the leading edge compared to less trees on the other end. In the analogy of a line of people, adding people to one end will move center that way as long as you don't add more to the other. The trees could grow each way or shrink each way and still show a movement, as long as one side is doing so at a different rate.

Perhaps they view themselves as a charity, and that spending is the goal.