Minnesota students’ scores on the ACT college entrance exam dipped slightly this year but were still higher than those of any other state where nearly all students take the test.

Graduating seniors in the class of 2018 earned an average composite score of 21.3 out of a possible 36, according to test results released Wednesday. That’s down from last year’s state average of 21.5, but still above the national average of 20.8 for the test that measures students’ college readiness in math, reading, science and English.

It was also enough to earn Minnesota a repeat distinction: the highest score out of the 19 states where at least 90 percent of graduates took the ACT. Nearly all Minnesota graduates — 99 percent — took the test this year.

Education Commissioner Brenda Cassellius said the state’s scores reveal that Minnesota students are “showing us that they are graduating high school with the skills they need to be successful in their careers or college experiences.”

“It is our goal that students are well prepared for their next step in life, whether it is securing their first job or attending the college of their choice,” she said.

In Minnesota, where the ACT is the most popular college entrance exam, students take the test at a rate well above the national average of 55 percent. Participation here has increased significantly in recent years, pushing the state’s average down. (In 2014, when only 79 percent of Minnesota’s graduating seniors took the test, their average score was 22.9.)

But even with a larger share of students taking the ACT, Minnesota has outperformed national averages on the benchmarks the ACT uses to assess preparedness for college-level courses. Nationwide, 27 percent of students met benchmarks in all four subject areas, compared to 30 percent of Minnesota students.

Minnesota students also scored higher than their peers in neighboring states with similar levels of test participation; Wisconsin’s average composite score was 20.5 and North Dakota was 20.3. But the state was outperformed by Iowa and South Dakota, where fewer students take the test. In South Dakota, where 77 percent of students took the test, the average composite score was 21.9. In Iowa, with 68 percent participation, the average score was 21.8.

Nationwide, the percentage of students who met benchmarks in math and English has been dropping over the last several years. Scores on the math test hit their lowest level in 20 years, a trend ACT CEO Marten Roorda called a “red flag,” noting the importance of math and science in the global job market.

“It is vital that we turn this trend around for the next generation and make sure students are learning the math skills they need for success in college and career,” Roorda said in a news release.

Cassellius noted that students who took the ACT two or more times scored significantly better — with an average score of 23.7 — than their classmates who took the test once. Minnesota schools provide fee waivers for students who qualify for free or reduced-price meals, including for those who want to take the test a second time.

Cassellius said she hopes to see more Minnesota school administrators encouraging students to take the test during both their junior and senior years of school.