eMarketer this week predicted that Google’s share of search ad revenues will drop in the US, while Amazon will grow over the next two years. Amazon surpassed Microsoft in 2018 to become the second-largest ad platform for search in the US.

According to eMarketer, the US search ad market will grow nearly 18% this year to reach $55.17 billion. Google’s share this year is 73.1%, but in 2021, the share will decrease to 70.5%, eMarketer predicts.

The eMarketer polling suggests that most product searches now begin on Amazon. Amazon has a share of 12.9% this year, growing to 15.9% by 2021.

“Amazon’s ad business has attracted massive increases in spending because advertisers can reach consumers during product queries, a time when they’re ready to buy,” eMarketer principal analyst Nicole Perrin said. “Amazon has also rolled out better measurement and targeting tools, making it even more attractive for advertisers.”

Walmart, Target, eBay, and Pinterest are included in the “other” category, on the image above.

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