BANGOR, Maine — Despite slight declines in Maine students’ performance during a recent round of national testing, they did better than the national average.

The Nation’s Report Card, which examines how students performed on the National Assessment of Educational Progress, or NAEP, was unveiled on Wednesday. That test is given to students in grades four and eight every other year at randomly selected schools, and is meant to serve as a common yardstick to compare how students stack up across the nation.

About 2,500 Maine students took the test last school year. Nationally, 279,000 fourth-graders and 273,000 eighth-graders puzzled over it. The report compares those results with those from 2013 and earlier.

In fourth grade, 41 percent of Maine students taking the 2015 test scored proficient or better, which is down from 47 percent two years ago. On the reading test, 36 percent of fourth-graders scored proficient, which is down one percentage point compared to the 2013 test. The national 2015 average was 40 percent in math and 36 percent in reading.

Maine’s eighth-graders also struggled with this year’s math test. Their proficiency rate dropped from 40 percent in 2013 to 36 percent in 2015. Their reading results dropped about two percentage points, from 38 percent in 2013 to 36 in the latest test. The national 2015 average was 33 percent in math and 34 percent in reading.

Those one-year snapshots, however, don’t reflect a trend on their own.

“To see the trend, you have to look further back,” said Paula Hutton, Maine’s NAEP coordinator.

In 2000, only 23 percent of Maine fourth-graders tested proficient in math, 18 percentage points less than 2015. Their reading proficiency has remained flat over that same timeframe.

In eighth grade, 30 percent of Maine students tested proficient in math in 2000, 5 percentage points lower than the latest test. Their reading scores, however, have fallen. In 1998, 41 percent of Maine eighth-graders tested proficient on the reading portion, which was better than the 36 percent in 2015.

“The fact that Maine stays pretty much around the national average is amazing considering the amount of money we have available in our classrooms is pretty minimal,” Lois Kilby-Chesley, president of the Maine Education Association, said Wednesday. She also stressed that tests are only one indicator of student success, focused at one point in time.

Maine’s results reflect some of what was seen nationally.

Average fourth- and eighth-grade math scores fell nationally for the first time, according to Peggy Carr, commissioner of the National Center for Education Statistics. The percentage of students who tested as proficient nationally fell, though by relatively small amounts. Grade eight math and reading, and grade four math each fell 2 percentage points. Grade four readers improved their proficiency by one percentage point.

Hutton, Carr and others associated with NAEP tests have said that some of the fluctuations in results could be attributed to changes in education standards across so many states in recent years — including Maine.

For example, as new standards are adopted, some students could start learning certain math concepts a year later than they had in the past after restructuring of learning plans under state standards.

NAEP is a 90-minute pencil-and-paper test that has been administered in U.S. schools since 1969. The test is issued through the National Center for Education Statistics, under the U.S. Department of Education.

“The greatest value of NAEP is it is a consistent, basic measurement that is designed to provide teachers, school administrators, parents, business and community members a look at how Maine is doing compared to other states,” Acting Maine Department of Education Commissioner Bill Beardsley said in a news release.

The data is broken down further to show progress in large urban school districts, such as Los Angeles, New York and Boston, but doesn’t include breakdowns of performance at the district level in Maine.

The report card also highlights the pervasive national trend that students from low-income families, or those eligible for the free-or-reduced-lunch program, perform worse on standardized tests than their peers. About 42 percent of Maine students are eligible for that program based on their family’s income.

Maine’s performance gap was among the smallest in the nation, with low-income students in grade four scoring, on average, 19 points lower on the 500-point test than their peers. For another example, eighth-graders from low-income households taking the reading test scored just 15 points lower than their peers on the test. In Washington, D.C., that gap was 38 points.

Nationally, the average gaps were in the mid- or high-20s.

Research has long shown that poverty can be one of the biggest influences on a student’s success or struggles in school.

“You can’t discount the socioeconomic status of the community, school or family” when evaluating performance on tests like these, Kilby-Chesley said.

Follow Nick McCrea on Twitter at @nmccrea213.