BEIJING -- The value of China's service-outsourcing contracts was $71.65 billion in the first eight months of the year, up 6.6 percent year on year, official data showed.

Regions along the Yangtze River economic belt saw robust development in service outsourcing during the period, said an official with the Ministry of Commerce (MOC).

The 11 provinces and municipalities along the belt posted total contract value of $28.17 billion in offshore service outsourcing, up 12.4 percent year on year and accounting for 61.8 percent of the total nationwide.

Service outsourcing in central and western China also saw fast growth, with contract value rising sharply by 44 percent to $8.61 billion, while that in eastern China only rose 2.9 percent year on year, data showed.

The MOC attributed the surges to the rising operating cost for companies in the east, as well as the return of talent from first-tier cities to second- and third-tier cities, resulting in the service outsourcing industry transferring from coastal regions in the east to central and western China.

The European Union was one of China's major clients for service providers, with year-on-year rise of 19.2 percent in the value of executed contracts in the first eight months, data showed.

China is the world's second largest service outsourcing provider after India. The State Council described the sector as a "green industry" that will be a new engine for tertiary industry and a boon to increasing employment.