Thank you for standing by, and welcome to Aflac's fourth quarter earnings conference call. Your lines have been placed in listen only until the question and answer session. Please be advised, today's conference is being recorded. I would like to turn the call over to Ms. Robin Wilkey, Senior Vice President of Aflac Investor Relations. Ma'am, you may begin.
Thank you, Catherine, and good morning, and welcome to our fourth quarter conference call. Joining me this morning is Dan Amos, Chairman and CEO. Kriss Cloninger, President and CFO. Paul Amos, President of Aflac and COO of U.S. Operations. Ken Janke, Executive Vice President and Deputy CFO. Jeremy Jeffery, Senior Vice President and Chief Investment Officer. Tohru Tonoike, President and Chief Operating Officer of Aflac Japan, is joining us from Tokyo. Before we start, I'd like to mention the safe harbor language to you. Let me point out that some statements in this teleconference are forward-looking within the meaning of the federal securities laws. Although we believe these statements are reasonable, we can give no assurance that they will prove to be accurate because they are prospective in nature. Actual results could differ material from those we discuss today.
We encourage you to look at our quarterly report for some of the various risk factors that could materially impact our results. I'll turn the program over to Dan, who will begin this morning with some comments about the quarter and our operations in Japan and the United States. I'll follow up with a few financial highlights for the fourth quarter and the year, then we'll take your questions. Dan?
Thank you, Robin, and good morning, and thank you for joining us. Let me begin a review of 2010 with Aflac Japan. Aflac Japan generated strong results throughout 2010. We were again pleased with the financial performance of our largest earnings contributor. Sales results were especially impressive considering the tough comparisons, particularly in the fourth quarter. Total new annualized premium sales in JPY exceeded our expectations and were up a solid 6.5% for the fourth quarter. For the full year, sales rose 11%. For the second consecutive year, we exceeded our annual sales goal of a 0-5% increase. Additionally, persistency improved for our large block of in-force business in Japan, rising from 94 to 94.2. An improvement in Aflac Japan's persistency rate contributes to the continued growth in premium income. Although Aflac Japan's benefit ratio rose in the fourth quarter, it improved for the full year.
The fourth quarter benefit ratio reflects reserve adjustments made to a closed block of dementia care business that we stopped selling almost 20 years ago. As we look to 2011, we expect further improvement in the benefit ratio, resulting in continued expansion of the pre-tax profit margin. In the first quarter of 2010, Japan's premium income grew 3.3% and improved to 4.4% for the fourth quarter, which contributed to a 3.8% increase for the full year. As expected, our pre-tax profit continues to expand, resulting in strong earnings growth for the year. The bank channel had a great year in 2010. Our innovative products aligned well with the product needs of the banks. Bank sales in the fourth quarter posted another record with sales of JPY 7 billion, which represents an increase of 140.4% over the fourth quarter of 2009.
Last quarter, I mentioned how we believe more banks and mega banks in particular, would step up their efforts in selling Aflac's products. That's exactly what happened. At the end of December, Aflac Japan was represented by 364 banks or more than 90% of the total number of banks in Japan. Of all the banks we now have enrolling our products, there's still many branches in their system that are not actively selling yet, which means there's still enormous sales potential. In addition to having a great year from a distribution standpoint, we saw success on the product side of our business. Aflac Japan has honed its ability to customize our product portfolio to appeal to the new market segments by enhancing the benefits of our existing product line. A good example is our expanding suite of medical products that we successfully created over the last decade.
In fact, the medical product category was the number one contributor to total sales for both the fourth quarter and the full year. You'll recall that in August of 2009, we launched New EVER, an updated version of our popular medical product. Promotion for the New EVER featured the Maneki Neko or Cat Duck advertising campaign that literally became an overnight sensation in Japan and prompted an incredible surge in the fourth quarter of 2009 medical sales. Although we saw a slight decline in medical sales compared to last year, this category generated a significant amount of new annualized premium. Importantly, we maintained our position as the number one seller of medical products in Japan, which confirms the continued popularity and demand for our innovative policies.
Not only was 2010 a year in which we maintained our number one position in medical sales, it also was another year where our cancer products dominated the market. Cancer insurance sales made a solid contribution to the total sales, accounting for 22% of the total sales for the year. We are introducing a new cancer policy called DAYS that replaces the base policy, Cancer Forte. This enhancement of one of our pillar products speaks to the changing landscape in cancer treatment, as well as our commitment to being the number one provider of cancer insurance in Japan. It's important to remember that the foundation of our product portfolio has been and continues to be cancer and medical products. This solid platform allows us to leverage our competitive advantages, such as branding, administrative efficiencies, and to grow our product offering and meet the evolving needs of consumers.
As the bank channel has become a larger contributor to sales, Aflac Japan has also been enhancing its product portfolio to better meet the needs of banks, including WAYS and child endowment products, which were key drivers to growth for the fourth quarter and the year. WAYS is a unique hybrid whole life product that can be converted to a fixed annuity, a medical coverage, or nursing care benefit when the policyholder reaches a predetermined age. WAYS was first introduced in 2006 and was revised for the bank channel in 2009. Sales of WAYS really took off in the fourth quarter, accounting for 13.6% of the total production. The real story can be seen in the phenomenal growth rates, which was 140%.