Winners/Losers:
This is the area-weighted IV (sum of area times average IV for each county) change that is averaged for all 5 GCM scenarios. This is one number that summarizes the potential fate of the species under a doubled CO₂ climate. A number of -100 would mean that all 5 GCMs are indicating that the species would be extirpated from the US while a number of 400 would indicate a four-fold increase.