The history of network marketing originated in the 1940s when California Vitamins discovered they could generate more sales by having many sales representatives sell small amounts of product compared to few representatives selling large amounts. They also found most new customers came through referrals. This led to the development of a commission structure and the birth of network marketing. In 1959, Richard DeVos and Jay Van Andel founded Amway, which was based on the same network marketing model and became very successful. Currently, there are over 50 million people worldwide involved in network marketing, generating nearly $100 billion annually. The network marketing industry has grown significantly and is predicted to continue growing as more companies adopt this model.