Tokyo stocks dropped Wednesday, as fears over a firming yen dented exporters and financial issues were sold on concerns over their earnings outlook amid lower Japanese long-term interest rates. The 225-issue Nikkei Stock Average ended down 347.29 points, or 0.89 percent, from Tuesday at 38,490.17. The broader Topix index finished 39.26 points, or 1.41 percent, lower at 2,748.22. On the top-tier Prime Market, decliners were led by insurance, mining and transportation equipment issues. The U.S. dollar was weak in the lower 155 yen range mostly in the morning, as recent soft U.S. economic data re…