Minnesota high school graduation rates flattened last year, but the state saw more students of color graduating in 2015, chipping away at the stubborn achievement gap.

In 2015, 81.9 percent of public high school seniors graduated in four years, compared with 81.2 percent in 2014, according to the Minnesota Department of Education.

For black seniors, 62 percent completed high school last year, compared with 60.4 percent in 2014. More Hispanic and American Indian students also graduated.

"Every percentage point, every increase, whether it's one decimal point or double digits, represents another student who is graduating high school prepared for their next step in life," Education Commissioner Brenda Cassellius said in a statement.

Denise Specht, the president of Education Minnesota, the state's teachers union, said the data released Monday show steady progress.

"But our state is still failing to give all its students the support they need to graduate from high school on time," Specht said. "We wish more students were graduating, especially students of color."

In the Twin Cities metro area, the area with the largest population of students of color, the biggest overall gains were in Spring Lake Park and Columbia Heights.

In the three largest metro-area districts, Minneapolis and Anoka-Hennepin saw improvement, while St. Paul's graduation rate remained flat. Bloomington saw the biggest drop, from 87 percent in 2014 (690 graduates) to 77 percent in 2015 (648 graduates).

Since 2010, Minnesota has closed the gap in graduation rates by 12 percentage points, according to the Education Department.

While the state did not see significant gains over last year, state officials say graduation rates have risen 6.4 percentage points since 2010, a noteworthy number considering there was a less-than-1-percentage-point increase between 2005 and 2010.

"Reaching our goal of a statewide graduation rate of 90 percent does not happen in one year," Cassellius said. "It is important to look at trends over time, and since 2010 we have seen the number of students graduating high school increase steadily every year."

Minneapolis up, St. Paul flat

The Minneapolis Public Schools, the state's third-largest school district, saw its most significant increase, compared with the previous five years. The district graduated 64 percent of its seniors, up nearly 6 percentage points from 2014. The district's rate remains one of the lowest in the metro area, higher only than Brooklyn Center's 48 percent.

Interim Superintendent Michael Goar said the district's graduation numbers include schools that other districts do not have, known as contract alternative schools, which mostly serve students at risk of dropping out. The graduation rate at its traditional high schools is about 79 percent.

"We still have a lot more work to do, but we are proud of the multiyear graduation rates," Goar said.

The district's academic plan calls for every high school to increase its graduation rate by 10 percentage points a year. Roosevelt High School met that goal, graduating 116 seniors last year. That amounts to 68 percent, a 10-point increase over 2014. Two years ago, the school's graduation rate was lower than 50 percent. It also went from having fewer than 43 percent of its Hispanic students graduate in 2013 to 75 percent in 2015.

"I am super psyched," said Roosevelt Principal Michael Bradley. "What we bet on is that if we focus on the human side of education, the data will take care of itself."

Henry High School in north Minneapolis posted the district's highest graduation rate, at nearly 87 percent. Southwest High graduated 86 percent of its 376 seniors.

The St. Paul Public Schools saw a six-year run of increases end. The 2015 graduation rate held fairly steady at 75 percent — a result that was a "little disheartening," said Joe Munnich, assistant director of research, evaluation and assessment.

He and others cited delayed graduations for students who attend alternative settings, although one traditional high school — Como Park — also saw a 4-percentage-point drop, to 84 percent.

Still, Como Park was one of seven district high schools to exceed the state average, an encouraging sign to Theresa Battle, assistant superintendent of high schools. She pointed to the district's embrace of AVID, a college-readiness program, as key to helping minority students and others stay on track.

The district wants to increase its overall rate to 80 percent by 2019, and despite this year's plateau, Munnich says it is a "very realistic" goal.

Suburban districts

Spring Lake Park (up 8 percentage points to 87 percent) and Columbia Heights (up 7 percentage points to 83 percent) both saw the highest increases in graduation rates.

St. Louis Park graduated 93 percent of its senior class, up from 88 percent in 2014. Principal Scott Meyers credited programs including one aimed at reducing the number of failing ninth-graders and an academic support program for minority students.

Other suburban districts saw their graduation rates dip.

Richfield saw more students dropping out in 2015, with 26 dropouts compared with seven in 2014.

Brooklyn Center had the highest dropout rate in the metro, at 23 percent.

Bloomington's falling four-year graduation rate comes from students choosing a five-year path to graduation, said the district's research director, David Heistad.

Some Hispanic students from Bloomington's Kennedy High School are selecting the option, Heistad said, contributing to the sharp decline in graduation rates for the group. The district's six-year graduation rate, meanwhile, has grown, he said.

State goals

The state has set a goal to have 90 percent graduation rates in all districts, with no student group falling below 85 percent. Black, Hispanic and American Indian graduation rates are below 70 percent.

Cassellius said that despite the flat numbers this year, she was encouraged to see rates for students of color increase. She said she is still confident that the state will meet, or come close, to meeting its goals.

Staff writers Beena Raghavendran and Anthony Lonetree contributed to this report.