For the past 10 years, adults ages 55 to 64 have been the group most likely to start a new business, according to a study released in May by the Ewing Marion Kauffman Foundation, which promotes entrepreneurship. And now that baby boomers are reaching retirement age, the trend is only going to grow. People are living longer and are more likely to pursue dream businesses rather than tend to their gardens when their workaday lives are done. About 80 percent of boomers claim they want to work in retirement, according to Sara Rix, senior policy adviser at the Public Policy...