6. Nebraska
> Ppt change in uninsured rate, 2012-2015: -2.9
> Expanded Medicaid?: no
> Pct. population without health insurance, 2012: 11.3% (16th lowest)
> Pct. population without health insurance, 2015: 8.4% (23rd highest)

Three years ago, 11.3% of Nebraska residents did not have health insurance, the 16th lowest rate of uninsured population in the country. The rate improved during the open enrollment period, and today 8.4% of Nebraska’s population is without insurance, one of the lower rates in the country. Despite having strong participation in the system, out-of-pocket costs for those opting in are relatively high. The average premium for a 40-year-old, nonsmoking man was $261, the 17th highest cost in the country.

Nebraska was one of a minority of states not to take advantage of federal incentives to expand Medicaid coverage. According to the HHS, had Nebraska expanded Medicaid, an additional 48,000 state residents would have been insured today, which would bring the uninsured rate down to 5.9%.

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7. Massachusetts
> Ppt change in uninsured rate, 2012-2015: -2.9 (approx.)
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 3.9% (the lowest)
> Pct. population without health insurance, 2015: <3.0% (2nd lowest)

An estimated 3.9% of Massachusetts residents did not have health insurance in 2012, the smallest uninsured rate at that time. As of March 2015, since the implementation of the Affordable Care Act, the percentage had fallen by an estimated 2.9 percentage points, the seventh smallest drop nationwide. At less than 3% as of March, the percentage of Massachusetts residents without health insurance remained the lowest in the country.

Massachusetts implemented its own health care reforms six years before the implementation of Obamacare. The state’s health insurance marketplace, Massachusetts Health Connector, has been helping to make insurance more affordable for state residents since its 2007 launch. Due to the state’s progressive policies regarding health insurance, relatively few state residents did not have health insurance in 2012, and the effect of the ACA was not as dramatic as it was in other states.

8. Delaware
> Ppt change in uninsured rate, 2012-2015: -3.2
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 8.8% (6th lowest)
> Pct. population without health insurance, 2015: 5.6% (11th lowest)

Nearly 80,000 Delaware residents did not have health insurance in 2012, or 8.8% of the state’s population — far lower than the national uninsured rate that year of 14.8%. As of March 2015, since the Affordable Care Act was implemented, that percentage had dropped 3.2 percentage points. While the improvement was more modest than the national decline of 5.7 percentage points, the uninsured rate remains among the lowest percentages in the nation. Earlier this year, Governor Jack Markell received approval from the HHS to take full control of Delaware’s health insurance marketplace.

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9. Minnesota
> Ppt change in uninsured rate, 2012-2015: -3.2
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 8.0% (4th lowest)
> Pct. population without health insurance, 2015: 4.8% (6th lowest)

Already before the ACA was enacted, Minnesota had a small uninsured population. An estimated 8.0% of Minnesota’s residents did not have health insurance in 2012, the fourth lowest rate. By March this year, the rate had fallen by 3.2 percentage points, the ninth smallest drop nationwide. The uninsured rate of 4.8% has remained among the lowest nationwide. In contrast, the percentage of Americans without health insurance fell by 5.7 percentage points over that period. Because of the ACA, 166,197 state residents have obtained health insurance, including new Medicaid recipients under the Medicaid expansion.

Minnesota implemented in 2013 its own health care exchange program, MNsure. The Minnesota Insurance Marketplace Act, which established the exchange program, stipulates that 1.5% of all premiums will fund MNsure’s operational expenses. This percentage increased to 3.5% at the beginning of this year.

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10. Oklahoma
> Ppt change in uninsured rate, 2012-2015: -3.3
> Expanded Medicaid?: no
> Pct. population without health insurance, 2012: 18.4% (5th highest)
> Pct. population without health insurance, 2015: 15.1% (3rd highest)

Oklahoma’s rate of uninsured residents dropped from 18.4% in 2012 — fifth highest at the time — to 15.1% this year. The improvement, however, was not as strong as in other states, and Oklahoma’s rate of its uninsured population was third highest as of March this year.

Oklahoma did not set up its own health care exchange and it did not expand Medicaid benefits. According to the federal government, if Oklahoma expands Medicaid coverage, an additional 123,000 residents would gain coverage, and the uninsured rate would fall to 11.9%.