Volunteer service in Beijing was worth an estimated 11.7 billion yuan ($1.76 billion) in 2015, representing 0.51 percent of the capital's GDP, a report by Beijing Normal University has found.

About 4 million people are registered as volunteers in Beijing, each working an average of 84.3 hours a year, according to the Value of Volunteer Service 2017 report released on Friday.

The university conducted an online poll of volunteers in six cities, including Beijing, Guiyang and Xiamen, and an offline poll in Beijing and Chengdu between July and September. Some 2,296 volunteers were surveyed in Beijing alone.

The report showed only 18 percent of registered volunteers are active, meaning they have provided volunteer services in the past year, suggesting more measures are needed to encourage volunteering.

"China has seen rapid growth in volunteer service due to support from governments, social organizations and private companies, and it could make a significant contribution to China's pursuit of sustainable development," said Guan Chenghua, a professor at the university.

He added that it is important to evaluate volunteering in China and share experiences with foreign partners.

The report was released at a panel discussion held by the United Nations Volunteers' headquarters and China office in cooperation with the China International Center for Economic and Technical Exchanges, Beijing Normal University and the Beijing Volunteer Service Federation.

It was announced that a volunteer alliance had been launched for the Belt and Road Initiative, and a group had been formed to unite organizations to present data and evidence about China at a global technical meeting on volunteering in 2020.

"I hope we can work together beyond this event to strengthen cooperation and share responsibilities," said Manon Bernier, the UN Volunteers manager for the Asia-Pacific region. "In doing so, I hope we can consider how UNV can help volunteer partners in this process to facilitate the implementation of the Belt and Road Initiative and the UN sustainable development goals."