Alphabet's (NASDAQ:GOOG) (NASDAQ:GOOGL) Google is forecast to see a decline in U.S. advertising this year due to a halt in travel amid the COVID-19 pandemic. 

According to a new report by research firm eMarketer covered by the media, Google is poised to see U.S. advertising revenue fall 5.3% in 2020, marking the first time it declined year over year since the research firm began tracking Google's ad sales in 2008. Google is faring better than the overall U.S. advertising market, which eMarketer predicts will see a 7% decline year over year in 2020. For all of 2020, eMarketer expects the tech stock to have U.S. ad revenue of $39.58 billion. For 2019, Google weighed in with ad sales of $41.8 billion, CNBC reported

Internet ad illustration

Image source: Getty Images.

A woman using a smartphone to search the Internet.

Google's advertising business in the U.S. is getting hit hard given its reliance on the travel industry. With travel coming to a halt earlier in the year amid the pandemic and with people still wary about boarding planes, advertisers have been reining in their spending. YouTube ad sales are expected to continue to grow this year, but it won't be enough to offset the overall decline in ad spending, noted eMarketer. 

"The biggest single culprit here is the travel industry, which has been both hardest hit by the pandemic generally, and has concentrated spending on Google in the past," Nicole Perrin, principal analyst at eMarketer, told The Wall Street Journal.  

At the same time that Google is experiencing a decline in ad sales, its rivals Facebook (NASDAQ:FB) and Amazon.com (NASDAQ:AMZN) are getting a bigger piece of the pie. eMarketer expects both companies to see an uptick in ad sales this year despite the pandemic. Looking out to 2021, eMarketer does expect Google's U.S. ads to pick up again, growing more than 20%. In 2022, it predicts ad sales will be up 11.8%, noted CNBC