That's not to say the rare detailed look Amazon management gave us into the numbers wasn't impressive -- it was. The release gave plenty of updated stats on its Pay with Amazon service, a platform that allows shoppers to make purchases from third-party websites using the payment information from their Amazon account. As the headline proclaimed, more than 33 million customers have now used Pay with Amazon to make a purchase. The platform's payment volume doubled in 2016. Active merchants accepting Amazon Payments grew 120% year over year. More than 50% of the customers who used the platform were also Amazon Prime members.