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Texas’ 28 largest cities — including Houston, Dallas, San Antonio, Austin, Fort Worth and El Paso — had a greater percentage of their population without health insurance in 2010 than the collective United States, according to the American Community Survey conducted by the U.S. Census Bureau.

There were 5.7 million Texans, nearly a quarter of the state’s population, who didn’t have health insurance in 2010. In comparison, 15 percent of the U.S. lacked health insurance, according to 2010 American Community Survey estimates.

The greatest number of uninsured Texans live in Houston, Texas' largest city, where 637,861 people, or more than 30 percent of the population, don’t have health insurance. This map shows the percentage of the population in Texas cities without health insurance in 2010. Zoom in to metropolitan areas and click on the cities’ dots to compare how many people lacked insurance in each area.

The Texas Tribune has also explored the demographics of the uninsured in Texas. Find more information on the complicated debate over how to expand insurance coverage in Texas here.

The American Community Survey data used for this interactive was compiled from monthly surveys taken over three years. In the sortable table below, you’ll find more information on all of the cities in the map, including the margin of error for each of the categories. You can read more on the methodology of the American Community Survey here or download the data using the New American FactFinder.