The Department of Education revised the graduation rate for last year’s graduating class after correcting a data error.

The state’s graduation rate dropped 1 percentage point to 81 percent — flat from the previous year.

The error — described as a "programming omission" — affected reported outcomes for 205 students at 37 high schools.

"Learning of data errors, particularly this late in the year, is frustrating, complicates communication with school faculties and communities, and disrupts improvement efforts," Superintendent Kathryn Matayoshi said in a statement. "There is no excuse for these errors. We have notified affected schools and I have directed a number of internal actions designed to ensure the accuracy and transparency of our data processes."

Individual school graduation rates factor into the DOE’s new school accountability system, known as the Strive HI Performance System, that tailors rewards, support and interventions for school improvement.

It largely replaces federal mandates of the No Child Left Behind law that required schools to meet rising reading and math proficiency targets or face sanctions. In addition to test scores, it credits schools for attendance, graduation and college-going rates, and closing the achievement gap between high-needs students — English-­language learners or those who are economically disadvantaged or have disabilities — and their peers.

Under Strive HI, schools are assigned a score out of a possible 400 points that generally determines where they place on one of five category "steps": Recognition, Continuous Improvement, Focus, Priority and Superintendent’s Zone.

Most of the 37 high schools whose graduation rates were corrected also had minor changes to their index scores, but no changes to their Strive HI classifications, the DOE said.