“We knew Covid would have an impact on these mental disorders, we just didn’t know how big the impact was going to be,” said Alize Ferrari, a lead researcher at the Queensland Center for Mental Health Research in Australia and co-author of the study, published Friday in the Lancet.

In a systematic review, researchers analyzed data from dozens of studies that reported the prevalence of major depressive disorder and anxiety disorders in the pandemic, calculating that each increased by 28% and 26%, respectively, last year globally. That’s tens of millions more cases of depression and anxiety, in addition to the hundreds of millions already occurring around the world. All told, the researchers estimated there were about 3,153 total cases of major depressive disorder per 100,000 people and 4,802 total cases of anxiety disorders per 100,000 worldwide in 2020, after adjusting for uptick associated with the pandemic.

“That’s not trivial, that number,” Ferrari said.