Washington Redskins quarterback Robert Griffin III poses with fans as he participates in the "Stop Bullying in its Tracks" campaign at Six Flags amusement park on April 2, 2015 in Upper Marlboro, Md. (Jonathan Newton/The Washington Post)

About one out of every five students in U.S. middle schools and high schools reported that they had been bullied in 2013, the lowest rate since the federal government began collecting data on bullying in 2005.

In 2013, 22 percent of students between 12 and 18 said they had been victims of bullying at school during the school year, compared to 28 percent in 2011, according to data released Friday by the National Center on Education Statistics, the research arm of the U.S. Department of Education.

Federal officials say bullying can take one of three forms:

● Physical — Hurting a person or possessions

● Social — Hurting someone’s reputation or relationships

● Verbal — Saying or writing mean things.

Researchers say students who are victims of bullying are more likely to struggle academically, abuse drugs and alcohol, get depressed and commit suicide.

New studies have found that the psychological impact of bullying can last for decades, and that people in middle-age who were victimized as children continue to struggle with depression, anxiety and risks of suicide.

“Even though we’ve come a long way over the past few years in educating the public about the health and educational impacts that bullying can have on students, we still have more work to do to ensure the safety of our nation’s children,” Education Secretary Arne Duncan said in a statement.

The Obama administration hosted the first White House Conference on Bullying Prevention in 2011 and has held regular summits on bullying. The education department has hosted webinars and produced training materials for bus drivers and teachers, among other things. A cluster of non-profit groups, public health initiatives and educational programs have sprung up with an aim at reducing bullying among young people.

Broken down by race and gender, the 2013 data show that a larger percentage of girls reported that they were bullied, compared to boys (24 percent vs. 19 percent) and 24 percent of white students reported being bullied, compared to 20 percent of black students, 19 percent of Hispanic students and 9 percent of Asians.

Students in the younger grades tended to report higher rates of bullying than in the older grades. Sixth-graders, for instance, reported the highest rate at 28 percent, followed by 26 percent of 7th graders, 22 percent of 8th graders, 23 percent of 9th graders, 19 percent of 10th graders and 20 percent of 11th graders.

The data comes from the School Crime Supplement to the National Crime Victimization Survey, which asks a nationally representative sample of students ages 12 to 18 if they had been bullied at school. The survey has been conducted every two years since 2005.