The proportion of U.S. adults without health insurance has declined about 5.6 percentage points since 2013, to 11.7%, according to an analysis released today by Gallup. Based on the Gallup-Healthways Well-being Index survey for the first half of 2015, the uninsured rate fell a collective 7.1 points since 2013 in states that expanded Medicaid to low-income adults and set up a state or partnership Health Insurance Marketplace, compared with 5.3 points in other states. Five states saw the uninsured rate drop at least 10 points since 2013: Arkansas, Kentucky, Oregon, Rhode Island and Washington. Seven states had uninsured rates of 5% or less in the first half of 2015: Rhode Island, Massachusetts, Vermont, Minnesota, Iowa, Connecticut and Hawaii.