More Americans took to the water in new boats this summer, often buying smaller, less expensive models, as the industry is showing signs of a recovery, Bloomberg reportedPurchases of powerboats - which include yachts, pontoons and fishing vessels - rose 18.9 percent in July from a year earlier, according to figures from Statistical Surveys Inc., a research company based in Grand Rapids, Mich. Even with mild summer weather and a cold winter, year-to-date sales are up 3.1 percent, the data show. The industry "is performing pretty well again" after bottoming in 2010, with smaller boats - those under 30 feet in length - showing particular strength, said Tom Walworth, president of Statistical Surveys. Boat purchases are highly correlated with consumer confidence and gross domestic product, according to Thom Dammrich, president of the National Marine Manufacturers Association in Chicago.