Migrant workers in Shenzhen send 24 billion yuan (US$2.9 billion) to their families each year, a report on China's regional economies says.

The figure was based on an estimate that 5.5 million migrant workers living in the city pay an average of 5,000 yuan each a year to their families. The report was compiled by the social sciences academies in Beijing, Guangdong and Shanghai, and was reported by the Shenzhen Economic Daily on Monday.

The report says migrant workers in the Pearl River Delta region contribute much to the economies in their hometowns by remitting part of their income to their families.

There are about 15 million migrant workers in Shenzhen, Guangzhou, Dongguan and other Pearl River Delta cities, the report says. The sum of money migrant workers pay to their families was estimated at 50 billion yuan each year, based on the average of 3,500 yuan each.

Editor: Catherine