BEIJING -- China Petroleum and Chemical Corp, the country's largest oil refiner, said on Sunday that its net profits for the third quarter dropped 9.38 percent year-on-year to 18.33 billion yuan ($2.91 billion).

Earnings per share shrank to 0.211 yuan in the third quarter from 0.282 yuan in the first half of this year, the company said in a statement filing to the Shanghai Stock Exchange.

The figures were calculated according to the international financial reporting standards, the company said.

But if calculated according to the Chinese financial reporting standards, Sinopec's net profit fell 7.5 percent year-on-year and stood at 18.25 billion yuan in July-September.

For the first three quarters, Sinopec's net profit tumbled 30.24 percent from previous year to 42.83 billion yuan according to the international financial reporting standards, and 41.95 billion yuan according to China's standards.

In the January-September period, Sinopec's crude oil output increased 2.32 percent from previous year to 245 million barrels, while natural gas production rose 14.69 percent to 438.4 billion cubic feet.

The output of refined oil reached 98.39 million metric tons, while sales of refined oil increased 5.56 percent to 128 million tons, it said.

In its half-year statement, the company once said it planned to produce 163.75 million barrels of crude oil in the second half and 293.07 billion cubic feet of natural gas.