U.S. Department of Labor: "Although many people believe that 80 percent of all small businesses fail within five years, statistics from the U.S. Census Bureau reveal a different story. The Census Bureau reports that 76 percent of all small businesses operating in 1992 were still in business in 1996. In fact, only 17 percent of all small businesses that closed in 1997 were reported as bankruptcies or other failures. The other terminations occurred because the business was sold or incorporated or when the owner retired."
Old data, but interesting, nonetheless!