During supplemental insurer and Motley Fool Stock Advisor pick Aflac's (NYSE:AFL) second-quarter earnings call, CEO Daniel P. Amos stated that 15% annual growth isn't as easy as it used to be. However, a weak Japanese yen and challenging trends in Aflac's largest market weren't enough to keep the stock from reaching an all-time high, or to derail its prospects through 2008.

The weak yen was the primary culprit for a slight fall in total revenue for Aflac's second quarter. Happily, earnings managed a couple-of-percent increase that topped analyst expectations. Investment gains and continued strong results here at home helped the company offset more sales challenges in Japan, a region that accounts for nearly 75% of quarterly operating income.

New premium sales in Japan fell by 2% -- also not as bad as analysts feared -- and the weak yen put total premium income growth into negative territory as well. Total revenue was flat, but favorable trends in existing business, such as lower claims costs, led to an operating earnings gain of nearly 7%, as profitability continued to improve in Japan.

The U.S. business continued to do well on nearly every front. New sales, premium income, and operating earnings all grew in the double digits. Overall, Aflac expects to grow operating earnings 15%-16% for all of 2007, with a 13%-15% gain foreseen for 2008. Indeed, Aflac is no lame duck.

To enhance traditional insurance, Aflac offers individuals additional coverage against the threat of illness and injury. This business has long-term appeal, especially as baby boomers age. Japan is no spring chicken, either; more than a quarter of its population is older than 60. Insurance peers such as Conseco (NYSE:CNO), Unum (NYSE:UNM), Assurant (NYSE:AIZ), and even mighty American International Group (NYSE:AIG) also sell competing products, but Aflac is the only pure play in the space. Given its track record of profitable double-digit growth, Fools may want to give this firm a further look.  

For related Foolishness:

Aflac is a Motley Fool Stock Advisor recommendation. You can find out why with a 30-day free trial to the Gardner brothers' market-beating service.

Fool contributor Ryan Fuhrmann is long shares of Aflac, but has no financial interest in any other company mentioned. Feel free to email him with feedback, or to discuss any companies mentioned further. The Fool has an ironclad disclosure policy.