The Hong Kong Federation of Education Workers on Thursday urged the government to improve the student-teacher ratio in schools, saying teachers’ workloads have become too much to bear.

The federation said it surveyed more than 1,200 teachers in November and 90 percent said they were highly stressed.

A happiness index for teachers also fell to 4.33 out of 10 – the lowest level in a decade.

The federation’s vice-chairman Tang Fei said half of the teachers reported that dealing with students’ mental health issues was stressful.

“Teachers’ mental health should also be a focus issue emphasised by the Education Bureau and the SAR government, instead of just focusing on students’ mental health,” he said.

Tang added that teachers’ working hours have been increasing, with half of them putting in more than 60 hours per week.

“One of the ways to improve teachers’ mental health is improving the student-teacher ratio,” he added.