To determine which area lost the most in percentage decline, we can compare the percentage declines presented for each location:
- "Mexico": 78-95%
- Central Mexico: 85-87%
- Valley of Mexico: 69-96%
The Valley of Mexico has a percentage decline of 69-96%, which is the broadest range, but its lowest percentage (69%) is still the lowest compared to the other regions.
The Central Mexico has a percentage decline of 85-87%, which is also significant.
However, the category "Mexico" has a range of 78-95%. When considering the upper limits of the ranges for clearer comparison, the Valley of Mexico has the highest potential upper limit of 96%.
However, since a narrower range indicates a more certain decline, Central Mexico shows a clear and sizeable percentage decline consistently between 85-87%, which is significant but with a clearer percentage than "Mexico."
Overall, if judged purely on the highest percentage decline, then the Valley of Mexico with its potential for a 96% decline would be the choice.
Thus, the area that potentially lost the most in percentage decline is:
Valley of Mexico.