BEIJING, May 20 -- China's service outsourcing industry saw a steady expansion in the first four months of this year, according to data from the Ministry of Commerce.

Chinese firms inked service outsourcing contracts worth about 683.1 billion yuan (about 97.1 billion U.S. dollars) in the January-April period, up 15.8 percent year on year.

The executed contract value stood at 461.2 billion yuan during the period, with a year-on-year increase of 19.1 percent.

Of the total, the value of offshore service outsourcing contracts rose 15.6 percent compared to the same period last year, reaching 386 billion yuan.

In terms of the executed contract value, offshore service outsourcing with the United States, the European Union and members of the Regional Comprehensive Economic Partnership expanded 18.9 percent, 21 percent and 24.4 percent year on year, respectively, in the first four months of this year.

Outsourcing refers to hiring an outside party to carry out services or produce goods typically undertaken by in-house employees.