More than 80 percent of Michigan students in the class of 2018 graduated on time, a slight increase over the last few years. It’s a good trend for Michigan schools, but previous data show that a large number of those students who did graduate likely weren’t college ready.

The state’s Center for Educational Performance and Information released graduation and dropout rate data Thursday. The highlights: The graduation rate was 80.64 percent for the 2018 class, up from 80.18 percent in 2017 and 79.65 percent the previous year.

When these students were juniors and took the SAT exam, just 35 percent of them had scores that indicated they’re college ready.

The data show that graduation rates, while an important gauge of school quality, doesn’t necessarily equate to readiness for life beyond high school. That’s evident given that the most recent data show that 27 percent of the Michigan graduates who enroll in college end up taking a remedial course — non-credit classes that teach students material they should have learned in high school. Michigan doesn’t have a graduation exam to ensure students have met standards when they graduate.

That could be an important factor going forward, given Gov. Gretchen Whitmer has made increasing the number of Michigan residents who complete postsecondary education — which could include college or a training program — a priority.

Of the 10 Michigan school districts with the largest number of graduates, only four saw improved graduation rates. The others declined slightly.

Here’s a look at their rates: 

  • Detroit Public Schools Community District: 77.27 percent, down from 78.22 percent in 2017
  • Utica Community Schools: 92.92 percent, down from 93 percent
  • Plymouth-Canton Community Schools: 90.37 percent, up from 89.47 percent
  • Dearborn City School District: 94.70 percent, up from 94.69 percent
  • Chippewa Valley Schools: 91.91 percent, down from 92.25 percent.
  • Ann Arbor Public Schools: 89.48 percent, down from 89.66 percent
  • Rochester Community School District: 96.81 percent, up from 96.05 percent
  • Warren Consolidated Schools: 81.83 percent, down from 84.5 percent
  • Walled Lake Consolidated Schools: 92.17 percent, down from 93.17 percent
  • Livonia Public School District: 92.60 percent, up from 92.28 percent

The drop in Detroit, though, may have more to do with the return of schools from the Education Achievement Authority, the now-defunct reform district that included some of the worst-performing schools in the city. The EAA disbanded after the 2016-17 school year, and its schools returned to the Detroit district. In 2017, the EAA’s graduation rate data wasn’t included with the district’s data. But in 2018, it was.

Detroit Superintendent Nikolai Vitti said a more apples-to-apples comparison would be to look at what graduation rates would have been if the district and the EAA had been combined in previous years.

“By this approach, the 2016-17 overall 4-year graduation rate would have been 74.17 percent, and the current 2017-18 graduation rate would be 75.5 percent,” Vitti said.

The statewide dropout rate increased from 8.65 percent in 2017 to 8.73 percent in 2018.

“Getting more students through high school and on to a postsecondary program will help us reach Gov. Whitmer’s goal of 60 percent of Michigan residents with a postsecondary credential by the year 2030,” Sheila Alles, the interim state superintendent of schools, said in a prepared statement. “We are heading in a positive direction.”

Search below to see the four-year graduation rates for all Michigan high schools

Schools without graduation rate data didn’t have enough students in their graduating classes for the state to publicly report their data.