Aflac Inc.'s (AFL) third-quarter profit nearly quadrupled on reduced investment losses and increased premiums.

Chairman and Chief Executive Officer Daniel P. Amos said, "I continue to be encouraged by our financial and operating performance so far this year, especially in light of the weak economic conditions."

He noted Aflac remains cautious about the U.S. economy, saying that U.S. premium growth won't rise 5% this year as planned. Japan's growth target should be met.

The company reported earnings of $363 million, or 77 cents a share, compared with $100 million, or 21 cents a share, a year earlier. Operating earnings, which exclude investment gains and losses, rose to $1.25 from $1.02. The company in July projected $1.19 to $1.22, slightly above analysts' then-expectations.

Revenue rose 23% to $4.53 billion. Analysts polled by Thomson Reuters recently projected $4.68 billion.

Premium income in yen grew 3.4% in the company's Japanese operations, Aflac's biggest business. It grew 19% in dollars. U.S premium income rose 3%.

Meanwhile, there remain concerns about Aflac's $8.3 billion in perpetual-debenture exposure, which UBS earlier this month calling it "still disconcerting." Aflac said in July it wouldn't record any write-down under statutory accounting because it believes the hybrid securities--which contain elements of equity and debt--will continue to make payments.

Aflac recorded $212 million of write-downs on them in the third quarter, again on a nonstatutory basis.

Shares closed Wednesday at $40.58 and were inactive after-hours. The stock is down 11% this year.

-By Kevin Kingsbury; Dow Jones Newswires; 212-416-2354; kevin.kingsbury@dowjones.com

Order free Annual Report for AFLAC Inc.

Visit http://djnewswires.ar.wilink.com/?link=AFL or call 1-888-301-0513