Investments into Amazon.com (NASDAQ:AMZN) stock paid off in spades this year. Shares have trounced the market in 2020 and produced massive returns for investors who simply held on to the dominant e-commerce player through all the stock market noise.

If you invested $5,000 in Amazon shares at the start of the year, you'd have $8,400 of the stock in your portfolio today, which translates into a return of about 68%.

A woman celebrates while sitting behind her laptop.

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The wider S&P 500 rose 14% in that time and the tech-heavy Nasdaq Composite jumped 38%.

AMZN Chart

AMZN data by YCharts

Amazon benefited from an unprecedented shift toward online spending that made its delivery network a more central part of many consumers' lives during the pandemic. Product sales hit $145 billion in the nine months ended Sept. 30, compared to $110 billion a year earlier. The tech giant's web services division also got a big boost as more commerce moved online in 2020.

The holiday quarter will bring the biggest challenge yet to Amazon's platform, but CEO Jeff Bezos and his team believe they're prepared for massive growth. Sales should land between $112 billion and $121 billion in the fourth quarter, they predicted, which means gains of between 28% and 38% to finish the year.

Sure, a slowdown is inevitable in 2020. But many consumers are likely to continue favoring digital shopping long after the COVID-19 threat passes. And that implies more wins ahead for the industry's biggest player.

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