Amazon should continue to grow at an "amazing" rate, with the e-commerce giant set to capture nearly 10 percent of total retail sales by 2020, according to Telsey Advisory Group, which initiated coverage at outperform.

"Amazon's customer-centric approach, relentless pursuit of efficiency in existing and new businesses, strong and growing Prime membership base, and advanced technology platforms have differentiated the company and made it a preferred shopping destination," analyst Joseph Feldman wrote in a note to clients Monday.

"The ongoing consumer spending shift to e-commerce and greater share of wallet via expansion in new and existing categories, such as apparel, grocery, home, healthcare, and media, should help," he added.

That spending shift will put Amazon's retail industry market share at 9.6 percent by 2020, the Telsey analyst wrote, saying that much of the growth will come from its investment in the grocery business following the acquisition of Whole Foods Market in 2017. Its share at the end of 2017 was 5.6 percent.

"We believe food and drug presents the largest multi-year growth opportunity for Amazon," Feldman wrote. "The shift to online grocery is being driven by consumers' increasing comfort with buying almost anything online, along with greater product availability and improvement in the supply chain to offer faster delivery.

"The rollout of Prime Now grocery, a service that delivers products in one-hour and two-hours, should be a game changer."

The company recently announced that it will raise the price of premium Prime membership to $119 a year from $99 on May 11. Prime benefits fall into five basic categories: shipping, shopping, streaming, reading and various extras. Membership now exceeds 100 million.

Telsey Advisory Group — founded by veteran retail analyst Dana Telsey in 2006 3 set a price target of $1,900 on shares of Amazon, implying 20 percent upside over the next 12 months. Shares were up 1.2 percent Monday.

Amazon's stock is up more than 35 percent this year, against the S&P 500's negative performance since January; shares are up nearly 70 percent over the last year.