It’s common knowledge that the COVID-19 pandemic provided a boon to Amazon’s ecommerce and online marketplace business as well as its subscription services. But the top Internet retailer’s advertising platform continued to gain steam during our outbreak year as well, according to a recent analysis by digital market research company eMarketer.

Amazon’s advertising revenues grew by 52.5 percent last year, according to eMarketer, to total $15.73 billion. The e-commerce giant now accounts for 10.3 percent of all digital ad spending the U.S., compared to 7.8 percent in 2019.

U.S. digital ad revenue share, 2019 vs. 2020U.S. digital ad revenue share, 2019 vs. 2020.

eMarketer's analysis cites search revenues from Amazon's Sponsored Products and Sponsored Brands ads, as well as video ad revenues from properties such as Amazon Fire TV, Twitch and IMDb TV as reasons for the increased market share.

Amazon is the third-largest ad publisher in the U.S., behind Facebook (25.2 percent) and Google (28.9 percent).

eMarketer predicts Amazon’s digital ad business will continue to cut into Google’s leading share of the U.S. digital ad market, gaining by another 30 percent this year to surpass $20 billion by the end of 2021. Google’s digital ad business, meanwhile, will continue to grow.

eMarketer similarly predicts Amazon’s search ad business will grow to surpass $14.5 billion in 2021 to account for 19 percent of U.S. search ad revenues, second only to Google, which still maintains a sizable lead (56.8 percent) in the U.S. search ad market.

Amazon in 2019 was ranked the top digital media platform in terms of perceived ROI among advertisers, according to data from equities researcher Pivotal Research Group.