When compared to European countries and other developed nations such as New Zealand, Australia, and Canada, The United States stands out as the only nation without a publicly financed universal health care system.

Around one third of U.S. residents are covered by public programs, namely Medicaid and Medicare. Including private coverage, 88.3% of Americans have health insurance. Despite covering fewer residents, health care spending in the United State is far higher than in any other high income nation.

To determine the metropolitan areas with the best and worst health insurance coverage rates, 24/7 Wall St. reviewed the percentage of people under 65 in U.S. metro areas without health insurance in 2014 from the Census Bureau.

In Brownsville-Harlingen, Texas, 35.4% of residents under 65 do not have health insurance, the highest rate in the nation. This is more than 10 times the rate in Worcester, Maine where only 3.4% of residents of this age group are not insured, the lowest uninsured rate of any U.S. city.

88. Cincinnati, OH-KY-IN

> Pct. of adults under 65 without health insurance: 9.2%
> Poverty rate: 14.0%
> Pct. of adults in fair or poor health: 15.4%
> Medicaid expansion under ACA: YES

Under the Affordable Care Act, which went into effect on January 1, 2014, states could opt to expand Medicaid coverage to persons under 65 earning incomes of up to 138% of the federal poverty level. Prior to this law taking effect, a U.S. Supreme Court ruling in 2012 allowed states to opt out of this Medicaid expansion, and 19 states chose to do so. States that adopted the Medicaid expansion tended to have higher health insurance coverage rates than states that did not adopt the expansion.

Mostly, this holds true for cities within these states. Of the 25 cities with the highest uninsured rates, 24 are located in states that opted out of the Medicaid expansion. By contrast, 22 of the 25 cities with the lowest uninsured rates are located in states that adopted the Medicaid expansion.

Because the Medicaid expansion is aimed at providing health insurance to poor residents, opting out of the Medicaid expansion has had a larger effect on cities with greater levels of poverty. In eight of the 10 metro areas with the highest rates of uninsured people, poverty rates are higher than the national rate. In addition, the three cities with the highest shares of uninsured residents also have the nation’s three highest poverty rates.

In metro areas with lower health insurance coverage rates, residents tend to report feeling generally worse about their health than those with higher coverage rates. When asked about their health, 14% of adults nationwide rate their health as fair or poor. In 23 of the 25 cities with the lowest coverage rates, a higher share of adults report fair or poor health, and in three of these cities more than 30% of adults report such poor health. By contrast, only two of the 25 cities with the best coverage rates report worse health than the nation as a whole.

To identify the cities with the highest uninsured rates, 24/7 Wall St. reviewed the percentage of individuals younger than 65 without health insurance by metropolitan statistical area from the U.S. Census Bureau’s 2014 American Community Survey. Poverty rates in these areas are also from the American Community Survey. Percentages of adults reporting fair or poor health are from the 2015 County Health Rankings. Data for whether a state has accepted federal funds and adopted the Medicaid expansion under the Affordable Care Act are from the Henry J. Kaiser Family Foundation.

Click here to see the cities with the best health insurance coverage.

Click here to see the cities with the worst health insurance coverage.