A smaller percentage of Chicago high school students dropped out last year than ever before, the city announced Thursday.

The all-time low 6% dropout rate touted by Mayor Lori Lightfoot and CPS CEO Janice Jackson happened during the 2018-19 school year, under former Mayor Rahm Emanuel’s administration. Students last year dropped out of school at almost half the rate they did in 2011.

“Through expanding access to rigorous academic programs, increasing staffing to support student needs and magnifying our focus on equity, social and emotional learning and restorative justice, CPS is keeping more students in the classroom year after year and creating strong, student-centered schools in every neighborhood across the city,” Jackson said in a press release.

Lightfoot attributed the lower rates — down .4% from last year’s 6.4% — to teachers and staff members “transforming the lives of our young people.”

“The record-low one-year dropout rate is a reflection of our collective commitment to ensure that every student, regardless of zip code or household income is on a pathway not only to graduation, but also to a viable future post-graduation,” Lightfoot said in the release.

CPS said the decrease in dropouts from last year was spurred primarily by .5% decreases in the rates for black and Latino males, whose one-year dropout rates fell to 9% and 6%, respectively. In 2011, the district-wide dropout rate was 11.2%.

A CPS spokeswoman said a lot of factors contributed to the decrease, and that “it’s hard to point to one thing” that was done to keep kids in school. One of the efforts that has helped, she said, is the school district’s Freshmen On-Track program — a data point that Chicago researchers developed to determine whether or not a student is likely to graduate based on how they fared their freshman year.

That metric originated at the University of Chicago Consortium on School Research, whose deputy director Jenny Nagaoka said Thursday that last year’s low rates are “consistent with what we’ve been seeing over time.”

“The district is certainly aware of the needs, and they’re making efforts to help,” Nagaoka said. “I don’t know if what they’re doing is actually causing the improvements ... [But] it’s very encouraging to see positive trends over time.”