China Life Insurance, the country's biggest insurer, says its third-quarter net profit fell 70% from a year earlier due to weaker investment returns. Operating revenue was 76.97 billion CNY (11.3 billion USD), up 26.6% from a year earlier. But the company saw unrealized losses on securities investments totaling 8 billion CNY (1.2 billion USD). That compared to a gain of 11.1 billion CNY a year earlier. China Life said its foreign exchange losses due to the strengthening of the Chinese currency totaled 1 billion CNY (146 million USD) in the first nine months of the year.