By Deborah Levine
NEW YORK (MarketWatch) -- The dollar fell sharply against the Japanese yen and Treasury prices gave up slight gains from the European session in early U.S. trading Tuesday, before U.S. reports on home prices and consumer confidence. Bond traders also have their eyes on a Federal Reserve buyback and the government's sale of 5-year notes (UST5YR 2.02, -.00, -0.15%) . The dollar index (DXY 79.88, -0.48, -0.60%) , which measures the greenback against a basket of six major currencies, fell to 79.876 from 80.34 in North American trading Monday. The euro (EURUSD 1.3203, +0.0040, +0.3039%) rose to $1.3202, compared to $1.3148 Monday. The U.S. unit (USDYEN 81.9500, -0.8400, -1.0147%) traded at 82.01 Japanese yen, versus ¥82.81 Monday. Yields on 10-year notes (UST10Y 3.33, 0.00, 0.00%) , which move inversely to prices, fell as low as 3.31% earlier, then lately traded down 1 basis point on the day at 3.34%.