A new study put out by a Bethesda-based research division of Education Week found the graduation rate in Montgomery County to be the third-highest among the nation’s 50 largest school districts.

In the county, using 2005 data, 82 percent of the students graduated using a newly developed formula designed to include all students. In the past, underclassmen who dropped out of school or transferred out of the district were often lost in the final tally, giving districts a bloated figure.