Reading scores for fourth- and eighth-grade students held mostly steady last year, continuing a stubborn trend of minimal improvement across most racial, economic and geographic groups.

Scores on the National Assessment of Educational Progress, a series of federally funded achievement tests, rose in two states and the District of Columbia in grade four and in nine states for grade eight in 2009. Overall, the fourth-grade average remained unchanged while eighth-graders rose one point.

The average score for both grades was only four points higher than it was in 1992.

"Today's results once again show that the achievement of American students isn't growing fast enough," Education Sec. Arne Duncan said in a statement.

Fourth-grade math scores flattened last year and eighth-grade scores improved two points, scores that were considered stagnant compared to years of dramatic improvements; there has been a 27 point increase overall for fourth-grade students since 1990. By contrast, those leaps have never been seen in reading.

The test results come eight years after the enactment of the No Child Left Behind law championed by President George W. Bush, which set a goal for every student to read and do math at grade level by 2014. In 2009, just 33 percent of fourth grade and 32 percent of eighth-grade students scored at the proficient level in reading.