Amazon said on Tuesday that more consumers paid for Amazon Prime benefits in 2017 than any prior year.
But the company still has not revealed just how many members use the subscription services. Amazon did reveal that 5 billion items were shipped to Prime customers.
The announcement comes on the heels of a blockbuster year for the e-commerce company. Amazon posted its best "Prime Day," Cyber Monday and holiday season ever in 2017, with sales growing 60 percent year over year on Prime Day, and app-based sales up 50 percent year over year on Cyber Monday.
Amazon added on Tuesday that Dec. 30 was the biggest streaming day for the company's burgeoning content business, as Amazon's sales of smart Alexa speakers have boomed.
Amazon CEO Jeff Bezos has long said that loyalty and repeat purchases were a key part of Amazon's business, and over time, Prime programs have expanded to include Fresh food delivery, Pantry household supplies, Twitch game streaming and free books under Prime Reading. Some Prime members also got new discounts in 2017 thanks to Amazon's purchase of Whole Foods.