Hawaii is one of a dozen states that made substantial gains in high school graduation rates between 2002 and 2006, according to a new report by researchers at Johns Hopkins University.

Nationally the high school graduation rate remained flat at about 75 percent.

Hawaii's graduation rate rose 3.4 percent during the period from about 72 percent in 2002 to 76 percent in 2006, resulting in an additional 500 high school graduates.

The report, released yesterday by the Baltimore university's Everyone Graduates Center, found the largest gain was in Tennessee, where the rate rose to 72 percent from 61 percent. New York's rate increased to 67 percent from 64 percent.

Graduation rates increased by 6.8 percentage in Delaware (to 76 percent) and Kentucky (to 78 percent). Rounding out the list of states with substantial gains were South Dakota, Arkansas, Alabama, North Carolina, Hawaii, Missouri, Nebraska and New Hampshire.

The Associated Press and Star-Bulletin reporter Craig Gima contributed to this report.