- “The 80/20 Rule is one of the most helpful of all concepts of time and life management. It is also called the “Pareto Principle” after its founder, the Italian economist Vilfredo Pareto, who first wrote about it in 1895…He later discovered that virtually all economic activity was subject to this principle as well. For example, this principle says that 20 percent of your activities will account for 80 percent of your results, 20 percent of your customers will account for 80 percent of your sales, 20 percent of your products or services will account for 80 percent of your profits, 20 percent of your tasks will account for 80 percent of the value of what you do, and so on.” Eat That Frog, Brian Tracy, Page 20