1. Iowa
> Ppt change in uninsured rate, 2012-2015: -1.7
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 8.4% (5th lowest)
> Pct. population without health insurance, 2015: 6.7% (20th lowest)

More than 250,000 Iowa residents did not have health insurance in 2012, or 8.4% of the state’s population. As of March 2015, since the ACA was implemented, that percentage had dropped by 1.7 percentage points, the smallest drop in the country. In contrast, the percentage of Americans without health insurance fell by 5.7 percentage points over that period.

In many ways, Iowa was proactive in implementing the ACA. In 2012, Governor Terry Branstad wrote the U.S. Secretary of Health and Human Services at the time, Kathleen Sebelius, to make it clear that Iowa would pursue its own exchange despite some remaining questions and ambiguities surrounding the law. Additionally, the Iowa Department of Health established an interagency planning group between the departments of Public Health, Human Services, Revenue, and the Iowa Insurance Division to ensure a smooth implementation of the new healthcare law.

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2. Hawaii
> Ppt change in uninsured rate, 2012-2015: -2.2
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 6.9% (3rd lowest)
> Pct. population without health insurance, 2015: 4.7% (5th lowest)

After open enrollment in the Health Insurance Marketplace began on October 1, 2013, health insurance coverage in every state increased. The improvement in Hawaii was relatively modest, likely because of the state’s already high insured rate. Hawaii enacted laws to create a near-universal health care coverage system in 1974, the first state in the nation to do so.

The percentage of Hawaii’s population without health insurance decreased by 2.2 percentage points from 6.9% in 2012 to 4.7% in March of this year, the second smallest decrease nationwide. Over the three-year period, an estimated 28,700 Hawaiians have obtained coverage. Hawaii is one of many states with a state run health insurance exchange, Hawaii Health Connector.

3. Connecticut
> Ppt change in uninsured rate, 2012-2015: -2.3
> Expanded Medicaid?: yes
> Pct. population without health insurance, 2012: 9.1% (8th lowest)
> Pct. population without health insurance, 2015: 6.8% (21st lowest)

There were 321,972 Connecticut residents living without health insurance in 2012, or 9.1% of the state’s population — the eighth lowest uninsured share at that time. As of March 2015, since the Affordable Care Act was implemented, that percentage had dropped by 2.3 percentage points to 6.8%, the 21st lowest uninsured rate. However, Connecticut was one of just two states where the number of residents who qualified for health insurance under the Medicaid expansion was not available. If new Medicaid recipients were factored in, the improvement would have been larger.

Connecticut was also one of eight states to accept responsibility for implementing its own exchange program and expanding Medicaid. Partially due to the state’s early implementation, Connecticut received more than $200 million in federal grants.

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4. South Dakota
> Ppt change in uninsured rate, 2012-2015: -2.4
> Expanded Medicaid?: no
> Pct. population without health insurance, 2012: 11.5% (19th lowest)
> Pct. population without health insurance, 2015: 9.1% (20th highest)

An estimated 11.5% of South Dakota residents did not have health insurance in 2012, a smaller share compared to the national share of 14.8% at that time. By March this year, the percentage had fallen by 2.4 percentage points. The improvement was far lower than the nationwide decline in the uninsured rate of 5.7 percentage points. Now, 8.6% of South Dakotans do not have health insurance, inline with the nationwide share of the uninsured population.

Governor Dennis Daugaard announced in 2012 that South Dakota would not manage its own exchange program. Uninsured residents need to go to the federal exchange site in order to purchase health insurance.

5. Alaska
> Ppt change in uninsured rate, 2012-2015: -2.7
> Expanded Medicaid?: Yes
> Pct. population without health insurance, 2012: 20.5% (3rd highest)
> Pct. population without health insurance, 2015: 17.8% (the highest)

Alaska was one of just four states where the 2012 share of the uninsured population, at 20.5%, exceeded the 20%. By March this year, the percentage of the uninsured residents had fallen by 2.7 percentage points, less than half of the 5.7 percentage point decrease nationwide.

Due to the findings of a state-run study on health insurance exchange planning, Governor Sean Parnell said that Alaska would not establish its own insurance marketplace. Uninsured Alaskans need to go to the federal exchange in order to enroll. While Alaska also did not initially accept the federal offer to expand Medicaid, Parnell recently notified the legislature he will accept the funds. Alaska had the highest average health insurance premium for a 40-year old non-smoker, at $475 a month.