Amazon's Prime Day 2019 shopping extravaganza is just days away. But there may be fewer people shopping than Amazon would like.
Amazon's Prime subscriber growth is slowing in the U.S, according to a study published Thursday by market research firm Consumer Intelligence Research Partners (CIRP). At the end of June, there were 105 million U.S. Prime members, up 11% from 95 million a year earlier.
Subscriptions to Amazon Prime grew the most in 2016 and 2017, when membership grew 43% and 37% , respectively, according to CIRP.
Amazon did not immediately respond to a Fortune request for comment. The company has not commented publicly about the number of Prime subscribers it has or whether the growth in their numbers has indeed slowed.
The study, which is based on responses from 500 people who bought products on Amazon.com between April and June, is in prelude to Amazon's two-day Prime Day that starts on Monday. The company has promised discounts on millions of products including smart home devices to clothes.
But since Prime Day is only open to Prime subscribers who pay the $119 annually to get free shipping, among other perks, the pool of shoppers is limited. And although 105 million subscribers is substantial, they only represent 57% of total Amazon shoppers in the second quarter. The remaining 43%—or about 80 million shoppers—aren't Prime subscribers and won't qualify for the discounts unless they sign up too.
In an interview with Fortune on Thursday, CIRP co-founder Michael Levin said that Prime Day has historically been a catalyst for people to sign up for Amazon Prime. But that hasn't happened as much this year as previously, partly because Amazon has pitched a large number of deals instead of a focus on deals in specific product categories.
"Other Prime Day events served to encourage new products, most notably Amazon Echo and the entire family of smart speaker accessories," Levin said. "This time, it looks a little more like a conventional retail promotion."
Whatever the case, Amazon is hoping for a huge number of orders. Last year, shoppers ordered more than 100 million products, making Prime Day 2018 Amazon's biggest shopping day ever. Anything less than a bigger day may be viewed as a failure—and perhaps an endorsement of its competitors' tactic of holding their own sales during Prime Day to cash in on the shopping frenzy.
Needless to say, with Amazon Prime Day around the corner, the e-commerce drama has hit a high water mark. Now we need to wait and see if Amazon can deliver on high hopes for a new record-setting sales event.
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