More than a third of students attended a school during the 2020-21 school year where 75% or more of the student population was of the same race or ethnicity, according to research from the Government Accountability Office released Thursday.

GAO also found 14% of students attended schools where 90% or more of the students were of a single race or ethnicity.

Additionally, the review of 10 years of data found when schools sever ties with an established district to create a new district — a process referred to as district secession — it resulted in the new districts having an underrepresentation of students of color. 

Specifically, GAO found new districts had, on average, about triple the share of White students, double the share of Asian students, two-thirds the share of Hispanic students, and one-fifth the share of Black students when compared to the remaining districts.

New districts were also wealthier than the remaining districts, the 39-page report found.

While some schools continue to be divided among race and ethnicity, the overall student population has grown more diverse. White students in the 1950s made up nearly 90% of the student body. In 2020-21, White students represented less than half of K-12 public school enrollment.

“We know that school segregation doesn’t just isolate low-income students and students of color; it also deprives them of equal access to educational opportunities and resources," Rep. Bobby Scott, a Democrat from Virginia who is chair of the House Education and Labor Committee, said in a statement.

The Century Foundation found, in a 2019 report, that students who go to racially and socioeconomically integrated schools have better academic outcomes.

Meanwhile, in New Jersey, a proposal in the legislature in the 2022-23 session calls for establishing a Division of School Desegregation, which would collect information on the racial, ethnic and economic demographics of students in each public school. 

The division would also analyze academic achievement of students attending highly segregated schools compared to those in more diverse schools.