The exam week for me usually results in two major outcomes: lack of sleep and some philosophical conclusions. It is maybe due to the too intensive cognitive processes going on in my brain or maybe because of the subconscious tendency to procrastinate, but exam week seems to be the best for making interesting observations, especially those not necessarily related to the subject of studying. This time I surprised myself and directed my intellectual efforts towards something quite useful, which partially helped me solve the sleeping shortage problem. So, here comes the story.


The more, the better?

The beginning of each block starts with big ambitions of reading everything what is supposed to be read: the thousand pages textbook, all the research papers, handouts etc. During the second week, I catch myself on having perfect notes and memos, but being stuck on the third chapter and feeling overwhelmed with amount of information to proceed. The reality of the third week is quite harsh and makes me realize that the ambitious vision of reading everything will not be really accomplished. At that time I start focusing my attention to only crucial readings: I intensively go through all the lecture and tutorial slides, old exam examples, I try to remind myself what the lecturer emphasized the most and concentrate on a though selection. At the end, it usually goes pretty well and I remember more than from readings of first week. Since this scenario repeated itself many times, I thought maybe there is some scientific theory behind it and I can use it in a more systematic manner. And here I remembered something called The Pareto Principle, also known as the 80/20 Rule.


What is the 80/20 Rule?

So the 80/20 Principle states that there is an imbalance between causes and results, inputs and outputs, efforts and rewards. The numbers 80/20 are an approximate estimation but serve as an illustrative threshold of this relationship. The typical and statistical pattern shows that around 80 percent of outputs result from 20 percent of inputs; that 80 percent of consequences flow from 20 percent of causes; or that 80 percent of results come from 20 percent of effort. This rule is very simple to comprehend but it is quite counterintuitive. We are programmed to think that all our achievements should be addressed to all the efforts we put in the task, that all our daily activities all equally important, all phone calls or messages are equally life-changing etc. But what if 80% of our problems can be solved by changing 20% of causes and if 20% of your energy can get you 80% of success?


Short history behind the idea

The pattern underlying the 80/20 Principle is said to be discovered in 1897 by Italian economist Vilfredo Pareto (1848-1923). He studied the wealth and income distribution in nineteenth-century England and found that 80% income and wealth is owned by about 20% of the people in his samples. The story says that he was inspired by a discovery that 20% of the pea pods in his garden produced 80% of the peas. However, Pareto did not make this principle famous. A management consultant Joseph Juran was actually the one who popularized this idea in 1941 and named it after Pareto. Juran, when working on quality control as a young engineer noticed that 20% of reported defects accounted for 80% of the defectiveness. He saw that the principle can be very helpful in solving multiple problems. Since then the idea became a vital principle of effective management. These are the few interesting concepts:

  • 80% of sales come from 20% of products
  • 80% of your complaints come from 20% of your customers
  • 80% of work is completed by 20% of the team
  • 80% of your happiness comes from 20% of people around you
  • 80% of your time you wear 20% of your clothes
  • 80% of the errors and crashes in Windows and Office are caused by 20% of the entire pool of bugs detected. pareto_principle.

Rules of 80/20 Rule

There are several inspiring messages you can take away from the Pareto principle.

Determine and select. Eliminate. Focus. Limit the time.

Determine and select. First of all, you have to precisely determine which of your activities, efforts or projects are crucial for you. It takes experience and some analysis to precisely capture what should be your priority and what should not. Richard Koch in his book “The 80/20 Principle” (1997) distinguishes between 80/20 analysis and 80/20 thinking. 80/20 analysis uses quantitative statistical methods to establish the precise relationship between causes/input/effort and results/outputs/rewards. It is useful especially in business, when for example determining which products are the biggest success and which company should get rid of. 80/20 thinking is based on intuition and estimation and involves some experience.


Remember to eliminate the unproductive part, the 80% which do not bring any value. As Tim Ferris, author of “4 hours work week” said: “Create not-to-do lists and cancel, fire, subtract, and eliminate, eliminate, eliminate. If you remove all the static and distraction, priorities become clear, execution becomes a one-item to-do list, and time management isn’t even necessary.”


This is the crucial part: you have to really focus on your crucial 20% of work that has to be done. Give your best in it, because this will determine 80% of the results. Strive for excellence in few things, rather than a good performance in many, but make sure to be really excellent in what you have focused on.

Limit the time.

The time pressure acts motivating in applying the 80/20 rule and is related to another principle, called Parkinson’s Law, which states: “work expands so as to fill the time available for its completion”. Therefore, the more time you give yourself, the more you will perceive the task as a difficult and complex one.

The biggest challenge of 80/20 rule it to remain consistent and focused on the priorities. People show this natural tendency of getting easily distracted and spending the time on just keeping oneself busy instead of actually doing things. Another challenge to overcome lies in the feeling of unfulfillment. The rule says, 20% input of 80% output, but not 100%. Therefore, it is crucial to shift the perception from what we do not get to what we actually achieve. Besides, the rule cannot be literally applied in every context. In a grocery store, 20% of products bring 80% but it is not an aim to offer only few products on a shelf. 20% of songs is listened by 80% of fans, but we do not expect artists to put only blockbusters on their album.

The Pareto rule, when wisely applied, can give a good direction in time management. In the era of overwhelming information stream, being selective and focused is the only remedy for being able to actually process the inputs. When preparing for the next exam, determine beforehand: what do I want to take from this course? What is really expected from me to know? What I consider useful for my development?

To sum up, I just wonder: Was at least 20% of this article useful for you?