The nation’s high school seniors have shown no improvement in math and reading performance since 2009, and large racial achievement gaps persist, according to the results of a test administered by the federal government last year.

The results — released at an event Wednesday at Dunbar High School in Northwest Washington — detail student performance on the National Assessment of Educational Progress, or NAEP.

Also called the nation’s report card, NAEP is widely regarded as the most consistent measure of U.S. student achievement over time. Since the 1990s, it has been administered every four years to high school students and every two years to students in the fourth and eighth grades.

Younger students’ results on the 2013 NAEP were released in November and showed incremental progress, continuing a slow but upward long-term trend. Twelfth-grade performance, by contrast, has been stagnant in recent years, and senior achievement in reading has declined since the early 1990s.

Moreover, despite more than a decade of federal policies intended to close achievement gaps, the margin between white and Latino 12th-graders in reading remains as large as it was 15 years ago. The margin between black and white seniors has widened — not because white students have improved, but because black students’ average reading scores have fallen.

Achievement unchanged

On Monday, Education Secretary Arne Duncan celebrated the nation’s 80 percent graduation rate, its highest ever. But Duncan called the test scores and the achievement gaps “troubling,” and he said they should galvanize the country to redesign high schools.

“We must reject educational stagnation in our high schools, and as nation, we must do better for all students, especially for African-American and Latino students,” Duncan said in a statement.

The test was administered between January and March 2013 to a nationally representative sample of 92,000 12th-graders across the country. Results were made public for the nation as a whole and for 13 states that volunteered to participate in individual reports to find out more about their students’ performance.

Nationally, 12th-grade reading scores averaged 288 on a scale of zero to 500 — the same as 2009 and down four points from 1992. Not quite four in 10 students scored high enough to be considered proficient or better in reading.

In math, only 26 percent of seniors scored high enough to be considered proficient or better. The national average was 153 points on a scale of zero to 300 — no different from 2009’s score and up three points from 2005. The test underwent significant changes in 2005, making it impossible to make dependable comparisons with results from previous years.

There are competing explanations for the stagnation. Some critics of U.S. education policies say the flat scores are evidence that test-based accountability has failed to produce meaningful change. Others say the scores demonstrate the need for more rigorous Common Core State Standards.

Some analysts contend that the 12th-grade scores are evidence only of an unsurprising truth: that high school seniors are not motivated to try their hardest on tests in which they have no real stake.

“We all remember exactly how engaged your 17-year-old high school senior is,” said Frederick Hess of the conservative American Enterprise Institute. Hess said skepticism about high school results should serve as a reminder not to read too much into younger students’ scores, as well.

“We’re a little bit manic-depressive about test scores and what they tell us about reform efforts,” Hess said. “We get positive movement, and suddenly we have the secretary of education saying this proves that pre-K works or that teacher evaluation works. Then you see numbers that are not positive, and we start throwing our hands up and gnashing our teeth.”

Two states, Connecticut and Arkansas, made progress in both math and reading. West Virginia and Idaho demonstrated gains in math.

Maryland, Virginia and District were not among those jurisdictions for which results were reported separately.