The Pareto principle states that for many outcomes roughly 80% of consequences come from 20% of the causes (the “vital few”).[1]Other names for this principle are the 80/20 rule, the law of the vital few, or the principle of factor sparsity.
…The term 80/20 is only a shorthand for the general principle at work. In individual cases, the distribution could just as well be, say, nearer to 90/10 or 70/30. There is no need for the two numbers to add up to the number 100, as they are measures of different things, (e.g., 'number of customers' vs 'amount spent').
