Around 80 percent of all Iowa high school students graduated on time in 2006 — 11 percent more than the national average, according to a study by the Editorial Projects in Education Research Center.

And it’s a fair comparison, said Christopher Swanson, director of the center, part of a nonprofit organization that publishes Education Week.

The study aimed to first rule out the “usual suspects,” or ten socioeconomic factors usually associated with graduation rates, including poverty level, racial background, and size of the school.

“It is pretty challenging to get fairly accurate numbers on graduation rate,” said Terry Coleman, assistant principal at Iowa City City High School.

Furthermore, one can size up school districts according to criteria other than just graduation rate — they can compare as long as others share similar characteristics. This is what is calculated in the “district performance score,” which gives a more realistic view of a district’s performance.

Iowa City schools saw 90 percent of their students graduate, nearly ten percentage points above the state average. The schools earned an index score of 115 points, 15 over the national average. The district exceeded expectations the study assigned to it based on certain attributes.

“There has been a lot of interest in this analysis, which is good. We hope other groups will follow up with detail, to see exactly what has been going on,” Swanson said.

The study — released June 9 — found around three out of every 10 students nationally failed to graduate high school in 2006. The study projected U.S. public high schools lost 7,200 students per day in the 2008-2009 school year, though they couldn’t use numbers from that year.

Coleman points to recent programs targeting at risk students for the 5 percent increase in graduation rates from 1996 to 2006 — like the Fas Trac program, in which students are paired up with mentors.

However, Coleman said calculating graduation rates isn’t as simple as it seems. It is difficult to track a student who drops out of one district and enters another before graduating, for example.

In past years, some of the numbers have fluctuated wildly. In 2000, the graduation rate dropped over 20 percent from 1999, and then rose over 28 percent in 2001.

Coleman said the graduation rate has remained fairly stable, adding these dramatic fluctuations may have occurred around the same time the Iowa City school district stopped calculating graduation rates, and turning the numbers over the state officials.

The reported numbers since then, however, have remained fairly stable.

Coleman said he didn’t think the graduation rates will suffer in relation to a projected budget cut in the 2010-2011 school year, unless some of the school’s at-risk programs were cut.

“Things have significantly improved over what they were 25 years ago, I think we are working a lot harder and trying to address individual student needs,” Coleman said.