The number of students with disabilities in the nation’s public schools is growing, according to new federal data.

There were 7.2 million students ages 3 to 21 served under the Individuals with Disabilities Education Act during the 2020-2021 academic year, accounting for 15% of all students.

That’s up from the 2009-2010 school year when 6.5 million children were served under IDEA, representing 13% of public school students.

The figures come from the Condition of Education, an annual report issued by the U.S. Department of Education’s National Center for Education Statistics that details the latest data on education in America.

Of those with disabilities during the 2020-2021 school year, the most common diagnosis was specific learning disability, which affected a third of students served under IDEA, followed by speech or language impairment and a classification known as “other health impairment.”

Autism affected 12% of students with disabilities, while 7% had developmental delay, 6% had intellectual disability and 2% had multiple disabilities.

Denise Stile Marshall, CEO of the Council of Parent Attorneys and Advocates, or COPAA, a nonprofit that advocates for the rights of students with disabilities and their families, said that autism accounted for the most growth. She attributed that to improvements in early identification of children on the spectrum and changes to the criteria for diagnosing the condition that came in a 2013 update to the Diagnostic and Statistical Manual of Mental Disorders.

In addition, Marshall said that schools have focused more on what’s known as child find — or the process of identifying students with disabilities — in the last decade.

“We need qualified school teams to provide the educational supports and services the students need and schools need more resources because funding is not keeping up with this growth,” Marshall said. “Unfortunately, as I’m sure you know, getting identified does not always result in quality programs.”

The COVID-19 pandemic did appear to alter the number of students with disabilities in public schools, with the report showing a 1% drop in enrollment among this population in 2020-2021 compared to the previous year. At the same time, overall public school enrollment declined 3%.