CPS expects a 63 percent graduation rate for the 2012-2013 school year. File photo. View Full Caption Getty Images/Christopher Furlong

CHICAGO — Chicago Public Schools' graduation rates between 2011 and 2014 were lower than the district originally advertised, administrators admitted Thursday. The announcement came after a WBEZ investigation found that the district had been miscategorizing dropouts.

CPS reached artificially high numbers during those years because it didn't count out-of-system transfers and GED enrollees as "dropouts," despite their being categorized a such under state law, according to WBEZ.

Graduation rates are steadily increasing, according to new CPS data, with this year's rate up to 69.9 percent. But last year's rate, originally stated at 69.4 percent, was bumped down to 66.3 percent under the more accurate formula.

This is the first time CPS has acknowledged its inflated numbers, but the faulty data was unearthed months ago in an investigation by WBEZ and the Better Government Association.

"Earlier this year, questions were raised about whether the district’s graduation rates were skewed due to improper coding of student transfers at the school level," CPS stated in a release Friday. "CPS determined that changes were necessary to ensure dropouts were not coded as out-of-district transfers."

Despite the revision, administrators said they were encouraged by the solidly rising trend in graduation rates.

“We have to make sure that accountability comes with support,” CPS Chief Academic Office Janice Jackson told the Sun-Times. “What I can say is that I am encouraged by the upward trajectory, despite the changes we had to make.”

According to CPS data, 84 more students graduated in 2015 than in 2014, the smallest increase in years. That means the higher rate has more to do with a reduction in overall enrollment. About 3,800 fewer students attended CPS during the 2014-15 school year than did the year before.

In its Friday announcement, CPS also slightly revised down its freshman on-track rate, from 84.1 percent in 2013-14 to 82.6 percent. The next year's figure, according to the data, really did reach 84.1 percent.

CPS has yet to release school-by-school data for graduation and on-track rates.

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