There were 610 cases of depression recorded by Hong Kong children and teenagers aged from six to 17 in 2016-17, according to figures from local authorities.

According to the Hospital Authority, 350 children and teenagers aged from six to 17 were suffering from depression in the year 2013/14 and the number increased to 610 in 2016/17, a rise of 74%, Ming Pao Daily reported.

Most of the patients were teenagers aged from 12 to 17, but the report did not mention the exact figures. Meanwhile, a survey released by Queen Mary Hospital found that when asked the degree they think their children are suffering pressure, 35% of surveyed parents ranked their children seven marks or more out of 10.

More than half the parents said it takes two hours or more for their children to finish their homework every day. A total of 11.5% of the parents said their children needed another two hours or more for revision.

The survey, conducted from July to December last year, polled 2,038 parents from five primary schools on Hong Kong Island and 18 representatives from primary schools.

According to the Happy Kids Charter, launched by the team of Dr Phyllis Chan Kwok-ling, the head of child and adolescent psychiatry at Queen Mary Hospital, children aged five to 12 should sleep for 10 to 12 hours a day, news website HK01.com reported.

However, the survey showed that only 0.3% of parents said their children could have 10 hours of sleep a day, while the majority of children only get 8.26 hours of sleep. Dr Chan said children who need two hours or more to finish their homework suffer higher pressure than those taking less than two hours.

She said parents know the pressure their children are under and they still try to fill up their spare time with extra-curricular activities or tutorial classes. She suggested children should have more leisure time to do what they want and have time to relax, while schools should adjust the amount of homework.