designer491/iStock/Thinkstock(WASHINGTON) — The rate of uninsured Americans has hit a 50-year low, researchers say, as the percentage of Americans without health insurance has dropped sharply since the implementation of the Affordable Care Act.

In 2013, 45 million Americans under the age of 65 — 17 percent of the population — were without health insurance. Researchers with the Commonwealth Fund say that looking at the numbers from before and after the implementation of the ACA in 2014 shows a drop in the uninsured rate. In fact, every state except Massachusetts and South Dakota have seen the uninsurance rate drop each of the last two years.

Nine states that expanded eligibility for Medicaid coverage saw their uninsurance rates drop by half, while even states that didn’t expand Medicaid coverage saw drops of seven to nine percent.

Despite the increased number of Americans with health insurance, however, 28.5 million American adults remain uninsured.

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