HAIKOU, Nov. 18 (Xinhua) -- South China's island province of Hainan will construct two more offshore duty-free shops to promote tax-free consumption, according to the municipal bureau of commerce of Haikou, the provincial capital.

After completion within the year, the two new shops are expected to open next year, bringing the total number of offshore duty-free shops in Haikou to four.

The two existing shops are now in expansion, with the business area of the one in the airport to reach 9,000 square meters.

The province now has four duty-free shops, with the other two in Sanya and Bo'ao.

Sales of offshore duty-free shops in the province exceeded 12 billion yuan (about 1.8 billion U.S. dollars) from July 1 to Oct. 31, up 214.1 percent year on year after the province increased its annual tax-free shopping quota from 30,000 yuan to 100,000 yuan per person on July 1.