"The area bonus depreciates by 100% each level, until the bonus is entirely gone at level 5."
Well, if it reduces by 100% per level then it will be gone at level 2, not level 5.
WallyKZ: I assume they mean that the area difference start at a multiplicator of Standard, eg. 500 percentage points of standard area and then decreases 100 percentage points of standard area each level up.