Minnesota students continue to lead the nation in ACT college entrance exam scores, according to national data released Wednesday.

The state’s graduating class of 2015 earned the highest average composite score, 22.7 out of a possible 36, among states in which at least half the graduates took the test. The national average was 21.

This marks the 10th straight year that Minnesota’s students outscored the rest of the nation. A larger percentage of Minnesota students also met standards on three or more subjects than students across the country.

“We are pretty pleased to have this kind of sustained high performance for so many years out of Minnesota students,” Minnesota Education Commissioner Brenda Cassellius said. “It’s a great testament to our teachers and good programming that we have.”

More than 46,000 students, or 78 percent of the 2015 graduating class, took the ACTs. High school seniors who take the ACT are tested in four different areas: English, reading, math and science. Students can also take an optional writing test. Universities and colleges often use those scores in making college admission decisions.

Last year, the state required all juniors to take the exam, but those scores are not included in Wednesday’s report.

“For the tenth straight year, Minnesota students are number one in the nation on this important exam,” Gov. Mark Dayton said in a news release. “I congratulate our students, teachers, and school administrators for this outstanding achievement.”

Despite the high marks, the scores also reflect a deep divide in performance between white students and students of color in Minnesota. More than three-quarters of those who took the exam were white. The average composite ACT score for the white students was 23.7, compared to 17.6 for black students and 19.8 for Hispanic students.

According to test results, 62 percent of the state’s white students met standards on at least three of the academic subjects, compared to 17 percent of black students, a gap of more than 45 percentage points.

The test administrators say those gaps in Minnesota and across the country are troubling.

“We simply must do better,” ACT President Jon Erickson said in a statement. “It’s time to step up our efforts to provide them and all students with quality tools, skills and behaviors that prepare them for success.”

Cassellius said she was not pleased with the deep gaps in achievement, but was encouraged to see that an increase in the number of seniors taking the exam is mostly coming from students of color.

Last year, the state required all juniors to take the ACT in order to graduate because state officials said it would eliminate barriers to college access. But the Minnesota Legislature voted to cut the state’s testing budget nearly in half. The loss in funding meant the ACT will no longer be a graduation requirement.

Cassellius says she hopes the requirement for juniors to take the exam last school year will mean more of them will take the test as seniors to try to improve their scores.

“They’ve had the introduction to it,” she said. “Sometimes when you set the expectation, you set the trend.”