Amazon is expected to further increase its dominance of the US ecommerce market, according to the research firm Needham. Amazon currently accounts for 34% of all online sales in the US, but this is expected to reach 50% in 2021. It is thought that this growth will be fuelled by the increasing popularity of Amazon Prime, mobile penetration and third-party growth. Amazon Prime provides users with TV shows, music streaming and free 2-day shipping for ecommerce purchases, for 99 US dollars per year. Amazon Prime users are very loyal to Amazon, with 80% shopping on the site at least once a month, double the proportion of non-Prime users.