The average age for a member of China's labor force is 37.57, indicating that the country no longer has a youth-dominated labor force, according to a report by a leading Chinese university.

The 2015 China Labor-force Dynamic Survey, issued by the Center for Social Surveys at Guangzhou-based Sun Yat-sen University on Sunday, collected information on workers aged between 15 and 64 in 29 provinces and municipalities in China, news site jiemian.com reported Monday.

According to the survey, laborers aged between 15 and 29 account for 33.07 percent of the country's labor force, while people aged between 20 and 44 account for 32.8 percent.

The survey also found that the average salary of all workers who received income in 2014 was 30,197 yuan ($4,714), with an average annual growth rate of 9 percent.

The average annual salary of men was 33,697 yuan, while that of women was only 23,288 yuan.

Meanwhile, the working hours of China's labor force fell from an average of 50 hours to 45 hours a week from 2012 to 2014.

Self-employed entrepreneurs had the longest average working hours in 2014, while professionals and people who headed an organization or company worked the shortest number of hours.

The survey also said that foreign joint ventures, State-owned enterprises and government organs saw the biggest portion of workers working overtime.