The document presents a model for measuring country sustainability. It evaluates 14 factors on a scale from 0-100 to calculate an overall sustainability score from 0-1400. The factors cover environmental, social, economic, and governance areas. An initial linear model is created. Individual models are then developed for each factor, including linear, logistic, and inverse equations. Testing found the model rates developed countries with strong environmental policies highly and less developed countries poorly. The model is then applied to Afghanistan to analyze potential sustainability improvements from agriculture investments. Simulations predict such a program would increase Afghanistan's score the most over 20 years.