WASHINGTON (AP) Math and reading scores for Americas 9-year-olds fell dramatically during the first two years of the pandemic, according to a new federal study offering an early glimpse of the sheer magnitude of the learning setbacks dealt to the nations children.

Reading scores saw their largest decrease in 30 years, while math scores had their first decrease in the history of the testing regimen behind the study, according to the National Center for Education Statistics, a branch of the U.S. Education Department.

The dramatic setbacks, which erased two decades of progress in American test scores, reflect years of upheaval for the countrys education system. Schools shut down for months at a time amid COVID-19 outbreaks. Many children spent a year or more learning from home. Virus outbreaks among staff and students continued the disruption even after kids returned to the classroom.

The declines hit all regions of the country and affected students of most races. But they were most dramatic for the countrys most vulnerable kids. Students of color saw some of the steepest decreases, widening the racial achievement gap.

Much of the nations standardized testing didnt happen during the early days of the pandemic, so the findings released Thursday gave an early look at the impact of pandemic learning disruptions . Broader data is expected to be released later this year as part of the National Assessment of Educational Progress, also known as the Nations Report Card.