DES MOINES, IOWA (AP) -- Iowa high school graduates' average ACT scores increased slightly this year and remain among the highest nationally.

The results were released Wednesday by ACT, the Iowa City-based nonprofit that owns the college entrance exam.

The average composite score for Iowa students who graduated this year was 22.3, 1.1 point higher than the national average and tied for ninth best nationwide. Among the 26 states that had at least half their graduates taking the test, Iowa tied for second with Wisconsin. Minnesota was first with a 22.5 average score.

Iowa's score increased 0.2 percentage points from a year ago, when it ranked third nationally.

Scores range from one to 36 and cover math, science, English and reading. Colleges and universities use them to help determine admissions, scholarships and academic advising.

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