At least one in four people quit their job this year, and the share could grow before the end of 2021, according to data from the people analytics firm Visier. Its latest report accounts for voluntary departures from over 50 U.S. enterprise companies and upwards of 500,000 employees across industries.

While many employee surveys throughout 2021 forecast the share of people intending to quit, like a PwC survey indicating 65% of people were looking for a new job as of August, Visier data from January to August finds an annualized rate of 25% of people actually quit their job this year.

It’s a “substantial increase” even from 2019, says Ian Cook, Visier’s vice president of people analytics, when 22% of employees quit their job during a year of record turnover and a tightening labor market prior to the coronavirus pandemic.

“The volume at which people are changing jobs is unprecedented,” Cook tells CNBC Make It, which he says isn’t surprising given the way people have reevaluated their work and personal values during the pandemic, but it’s catching employers by surprise nonetheless.