80/20

Commonly known as the Pareto Principle, in business, the 80/20 philosophy states that 80% of a company's revenues are derived from 20% of it's resources or efforts - Pareto called it the law of the trivial many and the critical few.

Analyzing business data through an 80/20 lens results in data-supported decisions that drive dramatic growth in sales and profitability.

"For many events, roughly 80% of the effects come from 20% of the causes."
                                                                                                                 - Vilfredo Pareto