Historical data indicate that periods of enhanced instability and internal warfare usually extend for many years, with the median length... 10–15 yea… - Peter Turchin

Many of the historical "Golden Ages" were... golden... only for the elites, whose high levels of consumption were based on low real wages and falling consumption levels of the great majority...

Here we use the Cross-National Time-Series Data Archive for the US, UK, and several major Western European countries to assess these structural-demographic predictions.

Using these trends as inputs, the model calculated and projected... the Political Stress Indicator, which in the past was strongly correlated with socio-political instability.