A couple of years ago, the author of a report examining public school graduation rates wrote that North Carolina and other states were burying the truth under a mound of false data.

"It is astonishing that states are trying to pass off these numbers as legitimate," wrote Daria Hall of the Education Trust, a school reform advocacy group.

North Carolina, for many years, has published high school dropout rates as two percentages -- the ratio of dropout to students in grades 9-12 and the ratio of dropouts to students in grades 7-12. Because most students in grades 7-8 aren't even eligible legally to quit school, the second percentage is fairly meaningless.

More recently, the state Department of Public Instruction began focusing on the more legitimate percentage, the students who drop out in grades 9-12.

During the 2005-06 school year, the rate was reported at 5.04 percent, an increase from 4.74 percent the previous year. The 5.04-percent figure represents 22,180 students.

Of course, this rate still presents a false picture.

Each of those students in grades 9-12 could potentially drop out during each of the four years that they attend high school. So for the rate to be meaningful, the 5.04 percent figure would need to be considered cumulatively.

But even that figure, if multiplied by four, doesn't accurately reflect dropouts. Many ninth- and 10th-graders also aren't eligible to drop out. And students in some categories, including those who transfer into a "state/ district approved education program," simply aren't counted.

Criticism of the numbers hasn't been lost on the state Board of Education. Later this month, it will release for the first time a report examining four-year high school graduation rates.

School officials say the report will show the number of students who entered the ninth grade during the 2002-03 school year and those who graduated with a diploma by June 2006. The rate will take into account students transferring into and out of schools.

The percentage is expected to be "somewhere in the 60s," according to state Schools Superintendent June Atkinson.

Missed in the hullabaloo over how the state reports dropouts is that the department has been publishing a similar graduation rate for some time. It just hasn't been trumpeting the numbers.

Inside the N.C. Public Schools Statistical Profile published each year is a high school "retention rate," a ratio of the number of students who graduate to those enrolled in the ninth grade four years earlier.

The number doesn't take into account transfers into and out of school systems, so population growth somewhat skews it. Still, the rates provide a useful gauge to examine dropouts and graduates.

In 2004-05, the last year for which figures are available, the retention rate was 64.7 percent; three years earlier, it was 58.5 percent; in 1997-98, the rate was 60.4 percent.

The numbers reveal that dropout rates in North Carolina have been at unacceptable levels for a long time.

For just as long, some have wanted to hide the problem.

Scott Mooneyham writes for Capitol Press Association. Contact him at smooneyh@ncinsider.com