Vifredo Pareto, an Italian economist, formulated this well-known principle in 1895:

"In any series of elements to be controlled, a selected small fraction in terms of number of elements almost always accounts for a large fraction in terms of effect."

It is more commonly referred to as the 80/20 Rule, and has been applied to everything from business to horse racing. Twenty percent of your customers will account for 80% of your sales. Twenty percent of your products or services will account for 80% of your profits. Twenty percent of your tasks will account for 80% of the value of what you do.

Still wondering about horse racing?  Consider this -- 80% of races are won by just 20% of jockeys, and comprehensive studies have been developed to demonstrate that you increase your chances of winning by picking a jockey in the 20% bucket!

How does this apply to affiliate marketing? Most programs experience a situation where the top 20% of affiliate sales partners drive 80% of sales, producing enough revenue to cover the fixed costs of the program. 

Clearly, the top affiliate sales partners are very important to a program, and are key in driving sales through the site. For these reasons, many people in the affiliate marketing industry recommend that you focus on the top 20% and pay less attention to the 80% who are contributing less to total revenues. This strategy seems logical, right? 

In all of the examples provided above, common sense supports focusing on what is vital, and not on what is trivial. But this is not so with an affiliate marketing program, and there is inherent danger in focusing too much on the top tier merchant partners. 

While top affiliate sales partners are absolutely important, the mid- to low-tier affiliates – referred to as "core producers" - are crucial for driving incremental sales while lowering overall cost.

By the end of this paper, you should be able to answer the following questions:

1. Who are core producers and why are they are important?
2. How can you measure the value of your core producers?
3. What methods exist to help you maximize the value of your core producers?