Amazon, whose business has boomed in recent years, and added subscription services such as Prime that caters to customers hungry for specials and perks, recently announced how many Prime members they have. Previously a best kept secret, Amazon estimated to stockholders in a recent letter Prime members now count over 100 million globally. Not surprisingly, Prime is the driving force of the company’s delivery and content model.

Various analysts and journalists previously arrived at a figure much lower when attempting to estimate the number of Prime members. The company has grown at such a fast pace even the best guess, based on documented research, was far too low. Consumer Intelligence Research Partners had estimated some 80 million, with other companies and individuals reporting much lower figures. The Prime Membership, which offers free selections on video, audio, kindle, and free next day delivery on shipping has rapidly increased at a pace even analysts have trouble following.

Last December Amazon estimated that “in one week alone, more than four million people started Prime free trials or began paid memberships.” Since that time, Amazon has reached deep to expand its content users, even reaching out to previously untapped markets, such as its student base, and government welfare recipients. The company is doing so for the same reasons all companies tap into untouched, or little represented markets, which is profits. It’s also a fact that Prime members are reported by consumer groups to spend more money at Amazon than regular users. Consumer Intelligence Research Partners reported that nonmembers spend approximately $700, with prime members spending $1,300 annually.

Prime members start with a free trial, which lasts 30 days. After 30 days they are billed monthly at the rate of $12.00 per month, which is comparable to other similar subscription services. Members receive a huge library of video and Amazon Prime exclusive content. Selected audio and Kindle books are free, and for those that order items frequently from Amazon, free shipping is very attractive. By all indications, Prime memberships are not going to decline anytime soon.