In a 2011 paper, researchers at the Complex Systems Institute unveiled a model that accurately explained why the waves of unrest that swept the world in 2008 and 2011 crashed when they did. The number one determinant was soaring food prices. Their model identified a precise threshold for global food prices that, if breached, would lead to worldwide unrest.
The MIT Technology Review explains how CSI's model works: "The evidence comes from two sources. The first is data gathered by the United Nations that plots the price of food against time, the so-called food price index of the Food and Agriculture Organisation of the UN. The second is the date of riots around the world, whatever their cause." Plot the data, and it looks like this:
