California has made progress in school discipline reform, but some school districts are still suspending disproportionate numbers of Black students — and costing them valuable instructional time in the classroom, according to a report released Oct. 12 by researchers at UCLA.

The report, by the Civil Rights Project, looked at in-school suspension data from every district in the U.S. for the 2015-16 school year, the most recent data available through the U.S. Department of Education’s Office of Civil Rights.

Breaking down the data by race, gender and disability, researchers found that Black high school students nationwide lost nearly five times the number of instructional days that white students did due to out-of-school suspensions.

“We wanted to look at suspensions from an educational perspective,” said Dan Losen, co-author of the report and director of UCLA’s Center for Civil Rights Remedies. “What we learned is that suspension is a non-intervention. Nothing will happen except a loss of instructional time.”

California fared better than most other states in the UCLA report. In California, Black students lost 57 days of instruction per every 100 students in 2015-16. Missouri had the highest rate, with Black students losing 198 days of instruction.