About 3.3% of high school students identify as transgender and another 2.2% are questioning their gender identity, according to the first nationally representative survey on these groups, published by the Centers for Disease Control and Prevention on Tuesday.

Transgender and gender-questioning teenagers reported alarmingly higher rates of bullying at school, persistent sadness and suicidal thoughts and behaviors, according to the survey, which was carried out in 2023. About 1 in 4 transgender students said they had attempted suicide in the past year, compared with 11% of cisgender girls and 5% of cisgender boys.

“We have 5% of young people in the country who, because of the way they identify around their gender, are stigmatized, bullied, made to feel unsafe, feel disconnected at school and consequently have poorer mental health and higher risk for suicide than their cisgender peers,” said Kathleen Ethier, the director of CDC’s adolescent and school health division.

The data comes from the agency’s Youth Risk Behavior Surveillance System, a survey of more than 20,000 high school students in public and private schools in the country every two years. The 2023 survey was the first to ask teenagers in all schools whether they identified as transgender.

In the CDC’s survey, transgender and gender-questioning students reported feeling worse than even cisgender girls, who have drawn national attention to a crisis in mental health among young people.