YouTube is again touting the living-room TV as the fastest-growing screen in its device matrix, angling to get more advertisers to spend money on the platform.

In December 2020, more than 120 million Americans streamed YouTube and YouTube TV on their TVs — up over 20% from 100 million in March 2020, according to the Google-owned video giant. That lift, driven by the COVID-19 pandemic, helped fuel YouTube’s $6.89 billion in ad revenue in the fourth quarter of 2020, up 46% year over year.

Moreover, about one-fourth of YouTube’s logged-in connected-TV viewers last December watched YouTube and YouTube TV content almost exclusively (more than 90% of their total viewing) on TV screens.

YouTube is pushing its CTV reach ahead of the 2021-22 U.S. TV upfront buying season, when for the first time advertisers will be able to measure their YouTube connected-TV campaigns through Nielsen’s Digital Ad Ratings and Total Ad Ratings.

“Viewers are leaving behind traditional primetime, and we’re finding at YouTube that the new primetime is personal,” Neal Mohan, YouTube’s chief product officer, wrote in a blog post Wednesday. Streaming video “gives advertisers more places to reach those customers who have been abandoning TV for streaming platforms, including hard-to-reach viewers.”

According to Comscore data from June 2020, 82.5% of connected-TV viewing in the U.S. comes from five streaming services: Netflix, YouTube, Amazon Prime, Hulu and Disney Plus. Of those, only YouTube and Hulu sell ads, Mohan pointed out.

Mohan also cited a February 2020 study YouTube commissioned from research firm Talk Shoppe, which found 70% of YouTube viewers say they bought a product as the result of seeing the brand on YouTube. The video platform is testing a new integrated shopping experience that will let viewers make purchases directly on YouTube, Mohan announced last month.