21. Maine
> Ppt change in uninsured rate, 2012-2015: -4.2
> Expanded Medicaid?: no
> Pct. population without health insurance, 2012: 10.2% (11th lowest)
> Pct. population without health insurance, 2015: 6.0% (13th lowest)

Maine was the only state in New England that did not take advantage of the federal incentives to expand Medicaid. This is especially significant for Maine, which had the lowest median household income in the region at $46,974. Expanding coverage from the current threshold of the federal poverty level to 138% of the federal poverty level would cover an additional 28,000 Maine residents, according to HHS estimates.

In 2012, before the state’s Health Insurance Marketplace open enrollment period began, 134,709 Maine residents, or 10.2% of the population, did not have health insurance. Since then, the uninsured rate dropped by 4.2 percentage points. In contrast, the percentage of Americans without health insurance dropped by 5.7 percentage points over that three-year period. While average premiums were not significantly higher in states that did not expand Medicaid, the average monthly premium for a 40-year-old, nonsmoking man in Maine was $272, 11th highest of any state.

22. North Dakota
> Ppt change in uninsured rate, 2012-2015: -4.2
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 10.0% (10th lowest)
> Pct. population without health insurance, 2015: 5.8% (12th lowest)

After open enrollment in the Health Insurance Marketplace began on October 1, 2013, health insurance coverage in every state increased. The percentage of North Dakota’s population without health insurance decreased from 10.0% in 2012 to 5.8% as of March this year. In contrast, 9.1% of Americans do not have health insurance.

In addition to the adoption of the ACA and the expansion of Medicaid, North Dakota’s mining industry may also partly account for the decrease in the uninsured rate. People working in the mining industry are among the most likely to have health insurance compared to those in other industries. The number of mining jobs in North Dakota increased dramatically from 2012 through 2014. Mining employment started to contract at the start of the year, however.

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23. Utah
> Ppt change in uninsured rate, 2012-2015: -4.2
> Expanded Medicaid?: under discussion
> Pct. population without health insurance, 2012: 14.5% (20th highest)
> Pct. population without health insurance, 2015: 10.3% (14th highest)

Three years ago, 14.5% of Utah residents did not have health insurance, the 20th highest uninsured rate in the country. The rate improved during the open enrollment period, and today, 10.3% of Utah’s population is without insurance, the 14th highest share of uninsured citizens of all states. Out-of-pocket costs for those opting in are relatively low. The average premium for a 40-year-old, nonsmoking man was $207, the ninth lowest in the country.

Whether or not the state expands Medicaid is currently under discussion. If state officials move forward with the expansion, the HHS estimates an additional 74,000 state residents would gain health insurance coverage.

24. Mississippi
> Ppt change in uninsured rate, 2012-2015: -4.6
> Expanded Medicaid?: no
> Pct. population without health insurance, 2012: 17.0% (11th highest)
> Pct. population without health insurance, 2015: 12.4% (7th highest)

An estimated 17.0% of Mississippi residents did not have health insurance in 2012, well above the national share of 14.8% that year. By March 2015, the percentage had fallen by 4.6 percentage points to 12.4%, the seventh highest rate of an uninsured state population in the country.

Despite Mississippi Commissioner of Insurance Mike Chaney’s expressed intention to establish a state insurance marketplace, the governor and the state’s legislature rejected the plan. In addition, Mississippi did not expand Medicaid coverage, a decision that would have had a relatively large impact in the state as Mississippi had the lowest median household income in the country at $37,963. If the state opted to expand Medicaid, an estimated 165,000 residents would gain coverage, and the uninsured rate would fall to 6.8%.

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25. Illinois
> Ppt change in uninsured rate, 2012-2015: -4.9
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 12.8% (23rd lowest)
> Pct. population without health insurance, 2015: 7.9% (25th lowest)

After open enrollment in the Health Insurance Marketplace began on October 1, 2013, health insurance coverage in every state increased. In Illinois, the percentage of the population without health insurance decreased from 12.8% in 2012 to 7.9% as of March this year. Nationally, the uninsured rate fell 5.7 percentage points over the same period.

Opting for federal assistance in launching its state exchange, Illinois has received more than $150 million in federal grants to implement health care reforms. While nearly 600,000 Illinois residents are insured today as a result of the ACA, there is plenty of room for improvement. An estimated 1 million Illinois residents remain uninsured, one of the largest uninsured populations nationwide.