The data displays the number of paying Amazon Prime members in the U.S. as of June 2018. As of the last measured period, the source estimated 95 million Amazon Prime subscribers in the U.S., up from 85 million in June during the previous year. On average, Amazon Prime members spent 1,500 USD on the e-retail platform per year. June 2017 data also states that non-Prime members only spent 600 USD annually, which is still an improvement over the average 500 USD of annual Amazon spend as of June 2016.
