By 2020, one in four American workers will be over 55, according to the National Bureau of Labor Statistics. Though people tend to associate startups with millennials, new research shows that most entrepreneurs are actually baby boomers, with more 55-64 year olds creating companies since 1996 than their 20-34 year old counterparts. So where are the startup seniors most likely to succeed? The latest study has ranked the best cities according to older, small business owners. First place went to Portland, Oregon, with Houston, Texas taking second place and Atlanta, Georgia coming in third. Fourth and fifth place in terms of seniors' rankings were Dallas, Texas and Denver, Colorado.