Nearly 24 percent of Chinese people suffer from insomnia, and the number of young people affected is rising, according to a report released on Wednesday, which was World Sleep Day.

The report was released by Huami, a manufacturer of smart wristbands backed by Chinese smartphone maker Xiaomi.

Last year, increasing numbers of people aged between 13 and 35 were found to be suffering from insomnia, while the problem had eased among those aged over 64.

The report-the White Paper on the Chinese People's Sleep Quality in 2017-said 54.7 percent of people aged between 18 and 25 go to bed later than 12 am.

"Playing with smartphones is the main reason for the unhealthy bedtimes," said Wang Hui, who led a team at Huami that contributed to the annual report.

On average, Chinese people get up at 6:32 am after lying in bed for eight minutes after they wake up and fall asleep at 23:20 pm.

People in Shanghai have more difficulty getting up in the morning than those in other areas, remaining in bed for 10 minutes after they wake up.

However, Shanghai ranked fifth among the cities whose residents are most troubled by insomnia.

Wang said the research was based on data collected from nearly 50 million of Huami's wristbands, including the Mi band.

"All the bands are able to track users' movements, and the frequency of the movements can help our system judge whether the user is asleep or not," Wang said.

He said most of the products track the user's pulse, which is believed to be more accurate in analyzing sleep habits.

Tao Kun and Yang Xiao contributed to this story.