EUGENE, Ore. – Oregon students posted the worst graduation rate in the country for the class of 2013, moving down the list from number 46 last year.

Idaho was the only state to rank below Oregon’s 69 percent on-time graduation rate for students in 2013, simply because that state could not calculate its graduation rate, according recently released U.S. Department of Education data cited by OregonLive.com.

Oregon was ranked 46th  for its percent of graduates for 2012, with Nevada ranked last and three states that could not provide accurate figures.

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“Nevada improved its rate from 63 percent in 2012 to 71 percent in 2013, leaving Oregon far behind,” according to the news site. “After Oregon, the next-worse rate for the class of 2013 was in New Mexico, where 70 percent of students earned a diploma.”

Oregon’s dismal graduation rate is due mostly to pockets of students in certain areas that failed to graduate high school in four years, including “low-income students in Portland Public Schools, 43 percent of whom did not graduate in four years; Eugene students not in the gifted and talented program (38 percent did not graduate); low income students in Beaverton (38 percent); low income students in Salem-Keizer (36 percent); and male students in Portland Public Schools (36 percent),” Oregon Live reports.

Oregon education officials contend part of the state’s graduation rate problem is how it’s calculated, so they intend on changing those definitions to boost its numbers. Next year, state officials will include special education students who earn modified diplomas, as well as students who delay graduation to remain in high school to attend community college at public expense – two factors that when combined could increase the graduation rate by as much as 3 percent, though that won’t be enough to move it up the list.

“If Oregon’s graduation rate for the class of 2013 had been 3 percentage points higher, by including special ed graduates and students who had earned diplomas but deferred receiving them, the state’s graduation rate still would have been in the national basement,” according to the news site.

For 2013 graduates, an additional 3 percentage points would put Oregon tied with Georgia for the third-worst graduation rate in America, Oregon Live reports.

The news site points to anther factor that is also likely playing into Oregon’s graduation problems: chronic student absenteeism. Previous reports by The Oregonian show the Beaver State was the fourth-worst in the nation for students with more than 10 absences per year, with only Oklahoma, New Mexico and Montana with more chronically absent students.

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But there is at least one school district in the state that’s showing schools can effectively improve graduation rates of low-income students, which seem to be the least likely to graduate on time.

“Oregon’s best on-time graduation rate for low-income student in a school or district with at least 400 low-income graduates was in Hillsboro, where 74 percent of them earned diplomas in four years,” Oregon Live reports.

“The Oregonian has written many times about Hillsboro’s highly effective approach to monitoring students who are frequently absent and using a multi-agency ‘care team’ to help keep students in school and on track to graduate.”