(AP) — Attendance at this week’s CES gadget show in Las Vegas fell more than 75% compared to its previous in-person event two years ago, its organizer said Friday.

The Consumer Technology Association said on the show’s closing day that more than 40,000 people attended the multi-day event on the Las Vegas Strip. That’s less than a quarter of the more than 170,000 the CTA said were there for its 2020 convention.

The COVID-19 pandemic led the CTA to take 2021’s conference online, but the trade group decided eight months ago to bring a physical CES 2022 back to Vegas. That proved challenging amid a global spike in infections caused by the fast-moving omicron coronavirus variant that emerged late last year.

Conference attendees were required to wear masks on the exhibition floors that opened Wednesday and show proof of vaccination before they arrived.

But the rise in COVID-19 cases led a number of big tech companies to pull out of the conference in the weeks before the event.