By Deborah Levine
NEW YORK (MarketWatch) -- Treasury prices added to gains and the dollar inched up after an index on U.S. consumer sentiment fell to 66.6 in September, while analysts had expected a slight improvement. Yields on 10-year notes, (UST10Y 2.72, -0.04, -1.45%) , which move inversely to prices, fell 6 basis points to 2.71%. The dollar index (DXY 81.33, +0.08, +0.10%) , which tracks the performance of the greenback against a basket of six major currencies, rose to 81.332, from 81.239 late Thursday. Versus the yen, the dollar (USDYEN 85.6600, -0.1100, -0.1282%) bought 85.69 yen compared with ¥85.78 in late North American trading Thursday. The euro (EURUSD 1.3061, -0.0015, -0.1147%) changed hands at $1.3062, from $1.3080 in late Thursday action.