High School Graduation Rates – It Could Take A Ph.D. To Figure It Out

Courant education writer Kathy Megan reports:

Which graduation rate is more accurate?

In November, the U.S. Department of Education said that 83 percent of Connecticut high school students graduated in June 2011. That placed Connecticut among the top 18 states in the country – not a position state officials were crowing about, but better than the number released Tuesday.

A new calculation by the same agency puts the state’s graduation rate in June 2010 at 75.1 percent,  placing Connecticut well below the national average graduation rate of 78.2 – the highest in 40 years. (Never mind for now why the 2010 rate was released AFTER the 2011 rate.)

Yes, the numbers measure graduation rates for different years, but it would be unusual for the rates to jump by that much in one year.

That might be at least partly explained by the different methods used to calculate each year’s rate. But a federal official said Tuesday that he believes the 75.1 percent – based on statistics provided by the state – may be inaccurately low.

John Buckley, commissioner of the National Center for Education Statistics, said that the graduation number submitted by the state for June 2010 showed that more students earned diplomas than were actually enrolled. The number graduating was 115 percent of the number enrolled.

That didn’t make sense, so Buckley said his agency contacted the state for verification – but never heard back. (A spokeswoman for the state Department of Education said Tuesday evening she did not yet have enough information to comment on that matter.)  So the feds went ahead and “imputed” a new graduation rate, based on the graduation rate for June 2009.

It gets even more confusing.

Connecticut’s graduation rate for June 2009 took a significant plunge from June 2008. It had run along in the low 80^th percentiles -  82.2 percent in June 2008 – for years, but it dove to 75.4 percent in 2009. So the feds were extrapolating using that particularly low percentage.

“I’m actually asking our staff to track down and talk to the state again,” Buckley said. He said the drop-off from 2008 to 2009 is a number that he’d like “to dig deeper into, to understand if the numbers are true.”

In general, he said, the graduation rates released in the fall using a “cohort” method have been quite similar for most states to those released Tuesday using an older method.The cohort approach is preferred, but not all states have switched to it yet, Buckley said. Under the cohort method, the state keeps track of the actual students who entered in 9^th grade and follows them through  12^th grade to see who actually graduated. It’s thought to be the most accurate method.

The method that was used to compute the figures released Tuesday involves dividing the number who graduate in a particular year by the number of freshmen four years before. Because a comparatively large number of students stay back in ninth grade, the federal agency averages the numbers of students in eighth, ninth and 10^th grades reported five, four and three years earlier, respectively, to come up with the freshman class number.

Here’s a link to the report released Tuesday:  http://nces.ed.gov/pubs2013/2013309.pdf