YouTube will stop serving unskippable 30-second ads to users in 2018, Google announced on Friday.

The company will instead push its other unskippable ad formats, including the 6-second ad unit it launched in April and its 20-second ads. (We first spotted the story on Campaign.)

A Google spokesperson told Business Insider: “We’ve decided to stop supporting 30-second unskippable ads as of 2018 and focus instead on formats that work well for both users and advertisers.”

According to YouTube, more than half of its video views come from mobile users, where a 30-second ad can negatively affect consumers with a smaller data plan.

The video sharing website also faces competition from Facebook, which began testing mid-roll ads, allowing advertisers to insert ads after users have watched 20 seconds of a video, earlier this year.