WASHINGTON, D.C. -- Colorado placed No. 6 on a list of the happiest states in America. South Dakota and Vermont tied for the top spot in the Gallup-Sharecare 2017 State of American Well-Being Rankings, released Tuesday. The report measures how Americans feel about their physical health, social connections, finances, community and sense of purpose. "For those of us who follow this closely over the years, it's not a surprise to see South Dakota and Vermont sharing that perch.