Japan saw the worst suicide rate for those under 20 years old in 2018, with school-related matters such as poor academic performance cited as the most common reason among youth aged 10 to 19, the government said Tuesday in its annual paper on the topic.

The rate of suicide per 100,000 people hit 2.8 among those under 20, the highest since comparable data became available in 1978. But the rate at all ages fell to 16.5, the lowest since 1978, according to the 2019 white paper on suicide prevention measures.

The total number of those under 20 who killed themselves in 2018 increased 32 from the previous year to 599, bucking the trend of declines in suicides in all age groups.

The number of suicides in Japan fell 481 for the ninth consecutive yearly decrease to 20,840 in 2018, but the figure for those under 20 has been roughly flat since 1998.

Last year, no one under 10 took their own life. Of 568 people aged 10 to 19 who killed themselves with motives identified as written in suicide notes or elsewhere, 188, or 33 percent, cited school-related issues, followed by health problems at 119, or 21 percent, and family issues at 116, or 20 percent.

The results included cases of up to three identified motives per person. By types of school-related issues, poor academic performance was cited by 57, worries for the future by 46 and friction with schoolmates by 27.

Among elementary school students, many pointed to family issues. In the older age group, the most common reason for suicide among boys was academic underachievement.

Among girls, the biggest reason cited by junior high school students was discord with parents, while depression was the No. 1 cause for high school students and those older.

In the paper, the government said it is necessary to verify the effects of suicide prevention steps and review them while closely monitoring the situation of youth.

"We will make more efforts to achieve a society in which nobody is cornered into suicide by cooperating with other government ministries and agencies," Health, Labor and Welfare Minister Takumi Nemoto said at a press conference.

Among suicides in Japan by people of all ages, the most common motive was health-related, followed by economic and livelihood issues and family matters. Under comprehensive measures against suicides adopted in 2017, the government aims to reduce the overall suicide rate to 13 or less by 2026.

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