Dear kids.
One thing I recently picked up (but forgot where) goes roughly like this: Pareto posed the 80/20 rule as we know it, because it is stunning enough when you encounter it. But reality is much, much worse.
Actually, it is more like “20% of 20%” — wich is comes down to 4%.
Actually, it should be called the 96/4 rule. But Pareto anticipated that this would be just too much for people to swallow.
So, once you observed the Pareto principle in the wild for a bit… once you accepted it and started using it… start looking for 96/4.