Based on the information provided and typical patterns in population changes, here are the most likely responses:
Question 1: Which area lost the most in percentage decline?
Response: Valley of Mexico
Question 2: How many years did it take for this decline in population?
Response: 6
Question 3: What could cause such a massive decline in population?
Response: Disease
Please verify these answers with the actual data from the chart for complete accuracy, as it's not provided here for reference.