An package sits in a UPS truck in Palo Alto, Calif. As of 2014, the company is the biggest online retailer in the U.S., commanding about 20 percent of all e-commerceSmart Spending Avoiding Amazon, Palo Alto, USA

There seems to have been no stopping Amazon online last year.

Research firm One Click Retail estimated Amazon grabbed 44 percent of all U.S. e-commerce sales and 4 percent of total U.S. retail sales last year. That equals about $200 billion in sales for 2017. Investors seemed content with that and pushed shares of the e-tailer up 0.9 percent to an all-time high of $1,200.27 in midday trading.

“2017 was a very big year for Amazon,” One Click analyst Spencer Millerberg said.

Indeed. The year saw Amazon best itself, and by virtue every other retailer, through the various shopping holidays it has either engineered or promoted. First there was Prime Day, set in the retail doldrums of early July, with sales estimated by industry analysts to be around $1 billion. Then came Cyber Monday, which Amazon said was its biggest shopping day ever. And its “best-ever” holiday season followed, with sales surpassing the 2016 season, when holiday sales came in around $4.75 billion.

An Amazon spokesman declined to comment.

Overall sales throughout the year were led by categories like consumer electronics, a segment that includes things like laptops and headphones, and home and kitchen goods, which pulled in an estimated $8.5 billion and $5.5 billion in sales, respectively. But those aren’t Amazon’s growth drivers.

That distinction goes to categories such as luxury beauty, which Amazon defines as professional-level hair, makeup and skin-care products, and its growing stable of private-label brands covering everything from paper towels to athletic apparel.

Amazon’s luxury beauty sales grew 47 percent year-over-year, totaling around $400 million, according to One Click. For comparison’s sake, Ulta Beauty tallied $4.85 billion in sales and the Estée Lauder Cos. Inc. hit $11.82 billion in sales during their most-recent full fiscal years. Amazon’s beauty sales might be small in comparison, but the company’s offering is nowhere near as extensive and many prestige beauty brands are not keen to do business with a mass e-tailer.

Such a clear growth opportunity is likely why Amazon is said to have locked up a deal with Violet Grey, the online luxury beauty retailer and content platform.    

One Click doesn’t have specific sales data on some of Amazon’s newer private labels such as athletic brands Peak velocity, Rebel Canyon and Goodsport, but the research firm said it is clear Amazon is “intent to compete with brands such as Nike and Lululemon.”

But Amazon’s total apparel category, including intimates, jeans and outerwear, grew 32 percent by the third quarter, and One Click said the fourth quarter is expected to surpass that growth “significantly.”

In 2016, One Click estimated Amazon to have sold $3.4 billion in U.S. apparel and by October, sales of its women’s apparel brand Lark & Ro had hit $10 million for the year, while basic apparel under its Amazon Essentials brand reached $3 million.

Globally, sales through Amazon’s platform are thought to be much higher. Simeon Siegel of research firm Instinet said last month that Amazon’s total 2016 apparel sales likely equaled 10 to 20 percent of its revenue, or between $18 billion and $36 billion.

Moreover, as Amazon counts successful partnerships with brands like Calvin Klein and Levi’s, Siegel estimated that Amazon’s global apparel sales could top $85 billion by 2020, leaving other retail giants like Wal-Mart Stores Inc. and Macy’s Inc., with $25 billion and $22 billion in 2016 apparel sales, respectively, running to catch up.

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