WOODBURY - Recent data shows that the number of foreclosed homes being sold on Long Island has dropped significantly, but there has only been a slight decline in sales across the country. RealtyTrac, an online real estate marketplace, says almost 26 percent of home sales last year involved foreclosures, a decrease of 3 percent from 2009.In Nassau County, foreclosures dropped 16 percent in the last quarter of 2010, while in Suffolk County foreclosures were down 35 percent during the same time period.