Dollar falls against yen on U.S. yield drop, profit-taking

The U.S. dollar hit a 15-day low against the yen on Thursday as traders used the quiet holiday period to take profits on the dollar's recent gains, while a drop in U.S. Treasury yields on waning risk appetite reduced the greenback's appeal. The greenback had gained 11.5 percent against the Japanese currency between the Nov. 8 U.S. election and Wednesday.