What is 80-20 rule?

• The rule invented by Richard Koch.it is also known as Pareto principle. 
• The 80% outcomes come from the 20% of inputs.
• In business the 80-20 rule is often used to point out that 80% of a company's revenue is generated by 20% of its total customers. 

• It can be applied to wide variety of subjects. such as wealth distribution, personal finance, spending habits.

Real time examples:

• 80% of the farming was done by 20% of the farmers.