BEIJING -- Ping An Insurance (Group) Co, China's second-largest insurer, said Thursday its profit rose 13.8 percent year-on-year to reach 14.52 billion yuan ($2.28 billion) for the first three quarters of 2011.

However, the insurer's third-quarter profits fell 44 percent from one year earlier, pulled down by a drastic decline in investment returns amid volatile stock markets, the company said in a statement filed with the Shanghai Stock Exchange.

Ping An's assets hit 2.19 trillion yuan at the end of September, up 86.9 percent from the end of last year.

Premiums collected by the insurer rose 32.9 percent year-on-year to reach 159.96 billion yuan during the first three quarters.

The company said the profit margin of its banking unit increased significantly during the same period, with the sector contributing 36.64 percent of the company's total profit.

The company's shares opened 1.15 percent lower at 37.1 yuan in Shanghai.