Among ethnic groups, Hispanics and African-Americans saw the biggest declines in uninsured rates, with percentage point drops of 8.3 and 7.3 percent respectively since late 2013. But Hispanics remain, by far, the group least likely to have health coverage, with 30.4 percent of Hispanic adults uninsured as of early 2015.
Among age groups, adults ages 26 to 34 saw the largest decrease in their uninsured rate since late 2013, a 7.4 percentage point plunge. And among economic groups, people who earned less than $36,000 annually saw a much bigger drop in their uninsured rate compared to other groups. Since 2013, that rate fell by 8.7 percentage points to 22 percent last quarter.
In article summarizing the latest insured rate findings, Gallup.com noted that "an improving economy and a falling unemployment rate may also have accelerated the steep drop in the percentage of uninsured over the past year."
"However, the uninsured rate is significantly lower than it was in early 2008, before the depths of the economic recession, suggesting that the recent decline is due to more than just an improving economy," Gallup said.
The survey found that the percentage of people enrolled in health plans paid by themselves or a family member—as opposed to people in job-based health plans—grew from 17.6 percent in late 2013 to 21.1 percent in the first quarter of 2015.
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Enrollment in Medicaid also grew, from 6.9 percent of adults in late 2013, to 9.0 percent last quarter.
Although private insurance plans sold through government-run Obamacare exchanges, which signed up about 11.7 million people this year, get the lion's share of media attention, Medicaid has played a major role in driving down the uninsured rate. That is particularly true in states that expanded eligibility for that program to include nearly all poor adults.
The 2012 decision upholding much of the Affordable Care Act also said the ACA could not compel states to expand Medicaid. The Montana legislature in recent days has moved toward making the state the 29th, along with the District of Columbia, to adopt Medicaid expansion.