At least one explanation for the fact that the Fall of Rome is the only period of decline on the graph could be this: data becomes more scarce the further back in history you go. This has the effect of smoothing the historical graph as you extrapolate between the few datapoints you have. Thus the overall positive trend can more easily mask any short-term period of decay.
At least one explanation for the fact that the Fall of Rome is the only period of decline on the graph could be this: data becomes more scarce the further back in history you go. This has the effect of smoothing the historical graph as you extrapolate between the few datapoints you have. Thus the overall positive trend can more easily mask any short-term period of decay.
Eg see also the bronze age collapse: https://en.wikipedia.org/wiki/Late_Bronze_Age_collapse?wprov=sfla1