US stocks staged a furious late-day rally, to push the S&P 500 into positive territory, as the focus shifted from European debt woes to buying after shares hit six-month lows. Major US indexes had fallen more than 3 percent early in the session on growing questions about the stability of the European banking system after a small Spanish bank failed over the weekend. Strategists linked the rebound in stocks to strengthening in the euro. The euro's strength has been a proxy for risk appetite and confidence in the euro-zone economy. So the Dow Jones industrial average dropped 23 points, or 0.2 percent, to 10,044. The S&P's 500 Index ended flat, at 1,074. And the Nasdaq Composite Index shed 3 points, or 0.1 percent, to 2,211. The CBOE Volatility Index, known as Wall Street's fear gauge, fell 9.7 percent, to 34.6, after reaching an earlier high of 43.74. In economic news, US consumer confidence rose for the third straight month in May, to the highest in more than two years. But that was countered by a report showing single-family home prices dropping in the first quarter on renewed price pressure as federal aid faded away.