JACKSONVILLE, Fla. -

The nation's high school graduation rate is the highest since 1976, but more than a fifth of students are still failing to get their diploma in four years, the Education Department said in a study released Tuesday.

Nationally, the four-year graduation rate was 78 percent and dropout rate was about 3 percent overall, down from the year before. The dropout rate for male students was 3.8 percent.

In Florida, between 70.8 percent graduated within four years of starting high school, while the dropout rate is 2.3 percent. Georgia graduated 69.9 percent of its high school students within four years, while 3.8 percent drop out.

For females, it was 2.9 percent. The dropout rate was higher among males in every state. The percentage gap between male and female dropouts was largest in Connecticut and Rhode Island, at 1.7 percentage points.

SLIDESHOW: States with highest graduation rates

Many students who don't receive their diplomas in four years stay in school, taking five years or more to finish their coursework.

The study also shows that graduation rates were up for every race and ethnicity, but gaps persist among racial groups, the Washington Post reported. Asian students had the highest graduation rate at 93 percent. White students had an 83 percent graduation rate, American Indians and Alaska Natives had a 69.1 percent rate, and African Americans 66.1 percent.

The statistics are from the 2009-2010 school year -- the most recent number available.

Officials say the steady rise of students completing their education is a reflection of the struggling economy and a greater competition for new jobs.