What is considered 'extreme ranges' for McCrees fall off damage?

Falloff range for McCree's weapon is 35 to 55 meters, and the damage would fall off from 70 damage at 35 meters to 20 damage at 55 meters. Extreme range probably means beyond 55 meters of range, which is considered the highest possible distance where the damage is at the lowest.

EDIT: McCree's damage falls off starting 20 meters now.

Source for damage and damage falloff numbers: http://overwatch.gamepedia.com/McCree