Hong, a woman in her 30s living in Seoul, is having second thoughts about her U.S. stock investments. "I increased the share of U.S. stocks in my portfolio about two months ago because the Korean market was doing poorly. But the stronger won has left my returns below expectations. I'm not sure whether to sell or just hold the stocks for the long term," she said. Hong is not alone. The won's recent strengthening against the dollar has cut returns for many Korean retail investors holding U.S. stocks, as currency losses offset stock gains. The won-dollar exchange rate closed at 1,339.2 won per dollar on Thursday, down sharply from the 1,550-won range seen two months ago after several weeks of declines. The won's strengthening can significantly reduce returns even when U.S. stocks rise. For example, a 20 percent gain on a U.S. stock would translate into a return of only about 4 percent for a Korean investor if the won-dollar exchange rate falls by around 14 percent. The recent currency move has led some investors to consider selling their U.S. stocks as the won continues to strengthen. However