Updated

African-American elementary students in California were chronically truant at nearly four times the rate of all students during the last school year, according to a state report released Friday.

The report by the California Attorney General's office is the first time the data has been broken down according to race and income levels. Officials say such data is needed to address the problem.

Poverty and suspensions are contributing factors.

Overall, more than 250,000 elementary school students missed 10 percent or more of the 2013-2014 school year or roughly 18 or more school days.

The absences were highest at the kindergarten and first-grade levels when children learn to read, according to experts.

The study found 37 percent of black elementary students sampled were truant, more than any other subgroup including homeless students, and about 15 percentage points higher than the rate for all students.

Statewide, an estimated 73,000 black elementary students were truant last school year.

California law defines truancy as being absent or arriving more than 30 minutes late without a valid excuse three times in a school year. Students who miss 10 percent of the school year without good reason are considered to be chronically truant, which experts say increases their risk of failing.

Attorney General Kamala D. Harris has been pushing for the state to adopt a system that tracks the absentee rates of individual students. California is among only a handful of states that do not. Legislation for such a system is on the governor's desk.

The Attorney General's office teamed up with a private company, Aeries Student Information System, which broke down the data from 32 school districts. The study found almost 90 percent of the elementary students who missed 36 days or more of the school year were from low-income homes.

"Because the state is not collecting this critical information, the attendance crisis among African-American children has largely remained hidden," the report states. "Therefore, we cannot conclusively explain the stark contrast between African-American elementary students' rates of absence and that of nearly every other subgroup. We do know, however, that African-American children experience many of the most common barriers to attendance — including health issues, poverty, transportation problems, homelessness, and trauma — in greater concentration than most other populations."

Research has found students who are truant starting at a young age are more likely to drop out. Dropouts cost the state more than $46 billion dollars each year, including more than $1 billion in juvenile crime costs alone.

Hedy Chang, director of Attendance Works, a nonprofit that studies chronic absenteeism, said students in impoverished areas often suffer from greater health problems, such as asthma, perhaps because the home is near a freeway. Their parents may be working and not there to see them off to school, she said. Crime may be deterring some from going out in their neighborhoods or they may be traumatized by what they've witnessed and act out at school, leading to them getting suspended instead of getting the help they need to stay in school, she said.

Many school districts have started overhauling their get-tough policies on students who skip school to improve attendance and graduation rates.

The state's largest school district, the Los Angeles Unified School District, has implemented changes after a civil rights investigation in 2011 found black students were underrepresented in gifted and talented programs but overrepresented in suspensions and disciplinary actions.

Truancy experts say school districts have seen success by providing one-on-one support.

Anna Salazar, who works with high-risk youth in the Los Angeles Unified School District, said she has found a child may be skipping school over something as simple as being embarrassed about having to wear dirty clothes.

"Once I build a relationship with them, I've found it's often something as simple and as tangible as that — needing a clean shirt," she said.