Updated at 8:48 p.m. on Monday, Oct. 1, 2018, with more information.

More than 86 percent of Hamilton County students graduated in 2018 — the highest graduation rate since the state changed how the rates were calculated in 2011.

It's an increase from 84.6 percent in 2017 and moves the school district closer to the statewide average of 89.1 percent, according to a news release Monday from Hamilton County Schools.

"We have accomplished our community's highest graduation rate even as the state is holding students to higher expectations," said Bryan Johnson, schools superintendent, in a statement. "The graduation rate is one of many indicators of success for a school district and the latest to show the progression of Hamilton County Schools to becoming the fastest-improving school district in Tennessee."

Graduates In Our Region

' Tennessee's overall graduation rate: 89.1 percent

' Bledsoe County: 92 percent

' Bradley County: 92.2 percent

' Cleveland City Schools: 93.5 percent

' Coffee County Schools: 92.8 percent

' Franklin County Schools: 91. 2 percent

' Grundy County Schools: 92.2 percent

' Hamilton County Schools: 86.6 percent

' Marion County Schools: 87.1 percent

' McMinn County Schools: 93.5 percent

' Meigs County Schools: 98.3 percent

' Polk County Schools: 94.8 percent

' Rhea County Schools: 91.4 percent

' Sequatchie County Schools: 94 percent

Source: Tennessee Department of Education data, 2018

On Monday, Education Commissioner Candice McQueen and the Tennessee Department of Education released statewide data, announcing that the state's graduation rate of 89.1 percent held steady in 2017 and 2018 and remains the highest on record.

"Our schools and districts should be proud that once again we have hit our state's highest graduation rate on record while still holding our students to high expectations," McQueen said in a statement. "By continuing to raise the expectations, we are signaling that Tennessee students are leaving high school with the knowledge and skills to be successful in college and the workforce. This graduation rate is a testament to the work being done by teachers and students in schools across the state."

The state noted that 106 districts in Tennessee — 81 percent — have graduation rates of 90 percent or more. Of those districts, 44 of them have graduation rates of 95 percent or or more.

In Hamilton County, 2,758 students graduated in 2018. Graduation rates vary widely from school to school, though.

About 71 percent of the senior cohort at The Howard School graduated in 2018, a 5 percent increase from 2017 when 66 percent graduated, according to the Tennessee State Report Card, whereas 100 percent graduated from Chattanooga High Center for Creative Arts for the second year in a row.

Chattanooga School for the Arts and Sciences, Hamilton County Collegiate High, Signal Mountain Middle/High, STEM School Chattanooga and Ivy Academy all had graduation rates of more than 95 percent.

Ivy Academy also saw a large increase from 84.4 percent in 2017, to 97.1 percent in 2018.

Hamilton County High School Graduation Rates

' Brainerd High: 81.2 percent

' Central High: 84.8 percent

' Chattanooga Girls Leadership Academy: 89.3 percent

' Chattanooga High Center for Creative Arts: 100 percent

' Chattanooga School for the Arts and Sciences: 98 percent

' East Hamilton School: 92.6 percent

' East Ridge High: 92.6 percent

' Hamilton County Collegiate High: 98.1 percent

' Hamilton County High: 81.7 percent

' Hixson High: 84.8 percent

' The Howard School: 71.1 percent

' Ivy Academy: 97.1 percent

' Lookout Valley Middle/High: 92.9 percent

' Ooltewah High: 84.9 percent

' Red Bank High: 78.5 percent

' Sale Creek Middle/High: 94.2 percent

' Sequoyah High: 86.7 percent

' Signal Mountain Middle/High: 95.1 percent

' Soddy-Daisy High: 87.4 percent

' STEM School Chattanooga: 95.3 percent

' Tyner Academy: 89.6 percent

Source: Tennessee Department of Education data, 2018

Debbie Smith, principal of CCA, said the 6-12 school begins thinking about graduation well before senior year.

"We look at the curriculum starting in sixth grade as a whole curriculum, holistically, what we do from sixth grade all the way to senior year," she said. "Like making sure our curriculum scaffolds, building on what you learn, exposing students to the skills that are going to make them better as students, such as how to study, how to give presentations, how to have conversations, to ensure they're successful."

Red Bank High School had the second-lowest rate in the district — 78.5 percent, a 2 percent increase from 2017.

Students learning English and students with disabilities also trail the district's average. Only 67.1 percent of English language learners graduated within four years and one summer, compared to 87.6 percent of students who were not ELL students.

Only 64.7 percent of students with disabilities graduated, compared to 89.6 percent of students without disabilities.

The graduation rate data is the latest data released by the state this fall, including how schools rank compared to others across the stateTVAAS growth scores and TNReady scores.

Of the state's largest metro areas — Chattanooga, Knoxville, Memphis and Nashville — Hamilton County had the second-highest graduation rate. Knox County had an 89.8 percent graduation rate in 2018; Davidson County, which contains Metro Nashville Public Schools, had a 80.2 percent rate; and Shelby County had 79.2 percent.

Tennessee's graduation rate is about 8 percentage points higher than that of its neighbor Georgia, which had an overall graduation rate of 81.6 percent in 2018. The two states do not have the same requirements for graduation, though, as they vary from state to state.

Contact staff writer Meghan Mangrum at or 423-757-6592. Follow her on Twitter @memangrum.