The duopoly is losing some of its advertising dominance, albeit a very small amount. The combined share of Google and Facebook will drop in 2019, even as their revenues grow, according to eMarketer.
Google will fall to 37.2 percent from 38.2 percent last year, while Facebook will slip slightly to 22.1 percent from 21.8 percent.
Facebook continues to maintain its share thanks to strong demand for ads in Instagram Stories. The photo-sharing platform still benefits from the perception that it's less impacted by the challenges Facebook has faced, according to Debra Aho, principal analyst at eMarketer.
But the big winner of 2019 is expected to be Amazon, which continues to siphon share from Google and Facebook. Its U.S. ad business is on track to grow more than 50 percent this year, according to eMarketer, and its share of the digital ad market will swell to 8.8 percent this year from just about 4 percent last year. It share is expected to reach nearly 10 percent in 2020.
"Amazon has a major benefit to advertisers, especially consumer packaged goods and direct-to-consumer brands," said Monica Peart, forecasting director at eMarketer. "The platform is rich with shoppers' behavioral data for targeting and provides access to purchase data in real-time. This type of access was once only available through the retail partner, to share at their discretion. But with Amazon's suite of sponsored ads, marketers have unprecedented access to the 'shelves' where consumers are shopping."
As expected, digital ad spending will surpass traditional ad spending this year. And by 2023 digital is expected to account for more than two-thirds of all media spending.
Total digital ad spending in the U.S. will grow 19.1 percent to $129.34 billion in 2019, according to eMarketer, topping traditional spend by nearly $20 billion.
Mobile makes up more than two-thirds of digital, totaling $87.06 billion in 2019.
Overall, traditional ad spending in the U.S. will decline to 45.8 percent this year from 51.4 percent last year. Print will drop nearly 18 percent, while TV ad spending will decline 2.2 percent to $70.83 billion. The 2020 presidential election is expected to propel TV ad spending back into positive growth before falling again in the following years.