The U.S. Census Bureau found more people gaining health insurance in 19 states in 2011, but still with many disparities across ethnicities and income.
The Census' Bureau's 2011 Small Area Health Insurance Estimates show that the counties with the highest uninsured rates were concentrated mostly in southern and western regions -- south Florida, southern Georgia, southwest Arkansas, Texas, northwest New Mexico, southern Colorado, Montana, Idaho, southwest Nevada, and Alaska.
Those states, as well as California, Louisiana, Oklahoma and Mississippi, had statewide uninsured rates of over 20 percent in 2011, according to the Census data.
The counties with the lowest rates of uninsured residents were largely in midwest and northeast regions, "most notably in Iowa, Minnesota, Wisconsin, New York, Vermont, Massachusetts, Connecticut, and counties along the Pennsylvania/New Jersey border," the Census Bureau said.
At the county level, uninsured rates ranged from 3.1 percent, in Norfolk County, Massachusetts (south of Boston), to 46 percent, in Aleutians East Borough, Alaska.
State-level uninsured rates ranged from 4.1 percent in Massachusetts to over 25 percent in Texas -- with fluctuations over time for those states and others.
Between 2008 and 2010, amid the Great Recession, 29 states saw an increase in the ranks of their uninsured and only three states saw a decrease.
"This pattern changes from 2010 to 2011," the Census Bureau wrote in the data brief. Nineteen states had a "significant" decrease in their uninsured rates, among them California, Florida, New York and Texas, while two states (Maine and Missouri) saw an increase, and the rest mostly held steady.
The Census Bureau's data also includes estimates of insured rates by demographics.
In almost all states, males had higher uninsured rates than females, and in all states, minorities had higher uninsured rates than non-Hispanic whites. In every state in 2011, the Census found, the uninsured rate was highest for Hispanics, followed by non-Hispanic African-Americans, followed by whites.
At the county level, uninsured rates for Hispanics ranged from 10.7 percent to 43 percent; from 6.6 percent to 29 percent for African-Americans; and from 3.8 percent to 19 percent for whites.
The Bureau also offered some data on insurance rates by income level: 
The Census Bureau's Small Area Insurance Insurance Estimates are based on survey data combined with population estimates and administrative records from a variety of sources, including the American Community Survey, federal tax returns, and the annual County Business Patterns series.