Evaluation

• There is enough agricultural production to sustain the estimated ending population with a two-year storage requirement. Estimated production would not support the exponential population estimate after A.D. 1090.
  
  
• There is enough agricultural production to support the minimum estimated population with a two-year storage requirement in almost every year.
  
  
• If sustainable population units are converted to annual consumption units (no storage), there is enough agricultural production in almost every year to support the maximum estimated population and exponential growth, although there is a decreasing surplus.
  
  
• However, after A.D. 1100, there are not enough annual consumption units to support the population with a one-year storage requirement, even if the previous year surplus is utilized.

Conclusions

• There is adequate annual production to support the maximum archaeologically estimated population and, even, exponential growth starting with a population of 1,470.
  
  
• Abandonment is not due to inadequate precipitation. However, surpluses decrease with time, which may have led to a perception of inadequacy.
  
  
• However, these conclusions do not account for environmental degradation or loss of soil nutrients due to agriculture.