Two new reports underscore how much the Affordable Care Act has affected the number people without health insurance in the U.S., even as a big threat to that goal looms next week.
The first report, from the federal government, showed continued strong enrollment in Medicaid, the joint federal-state program that provides health care to the poor.
The second report, from the polling group Gallup, found a sharp drop in the uninsured rate, with just 13.8 percent of people lacking health coverage, the lowest level seen in the survey's seven-year history.
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The Medicaid report said that almost 10.8 million extra people had signed up in that program and the related Children's Health Insurance Program compared to the period just prior to the launch of the Obamacare exchanges, an 18.6 percent increase in average monthly enrollment during that time frame.
By the end of December, a total of nearly 69.7 million people were enrolled in Medicaid and CHIP nationally.
And again, the biggest gains in Medicaid enrollment came in states that had loosened eligibility restrictions on the program as allowed by Obamacare.
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States that have allowed nearly all poor adults to enroll in Medicaid saw a more than 27 percent increase in their Medicaid rolls, on average since last summer 2013, while those that didn't expand eligibility had an average increase of just above 7 percent.
Currently, 28 states and the District of Columbia have expanded Medicaid, while the remaining states have tougher restrictions on who can participate.
Robin Rudowitz, associate director for Medicaid and the uninsured at the Kaiser Family Foundation research group, said "It's a little bit hard to disentangle" how many of the new Medicaid enrollees were previously eligible but hadn't bothered to sign up before, and how many were newly eligible because their states had expanded the eligibility guidelines.
And "we also similarly don't have an estimate of how many of these new people were previously uninsured," Rudowitz said.
The launch of the Obamacare exchanges in the fall of 2013 has been credited with boosting Medicaid sign-ups. Although the exchanges sell private health insurance plans, many people became aware they could get Medicaid, which as a rule doesn't cost them anything, when they entered income data on the Obamacare exchange's application forms.
Another factor credited with driving Medicaid enrollment is the Obamacare rule requiring most Americans to have some form of health coverage or pay a fine.
Rudowitz said that enrollment in Medicaid historically grew an average of around 2.5 percent annually, and tended to spike during economic downturns and after changes in policies for the program.
But Rudowitz also said the 18.6 percent increase in Medicaid enrollment since Obamacare exchanges launched is significantly higher than the rises seen at the height of the most recent recession. From December 2008 until the December of the following year, there was an 8.9 percent increase in enrollment. From December 2009 through December 2010, there was a 5.9 percent rise.
And the rate of increase in Medicaid enrollments was just a mere 1.1 percent in the year up to December 2013, she said.
The Gallup survey that found the uninsured dropping from 17.3 percent to 13.8 percent in the last year showed that the biggest drops came in states that had expanded Medicaid and that also were either running their own Obamacare insurance exchange or were operating an exchange in partnership with the federal government.
Of the 11 states with the largest decreases in the rate of people without insurance, 10 expanded Medicaid and had established such an exchange instead of leaving all Obamacare enrollment functions to the federal HealthCare.gov exchange.
"Montana, which is tied for 10th, is the only exception," the report by Gallup noted.
Arkansas and Kentucky had the biggest decreases in the uninsured rate. Arkansas went from 22.5 percent to 11.4 percent, while Kentucky went from 20.4 percent to 9.8 percent.
Massachusetts had the lowest uninsured rate, for the seventh straight year, at 4.6 percent. Texas had the highest uninsured rate at 24.4 percent.
Last week, the Obama administration announced that around 11.4 million people had enrolled in private Obamacare plans sold through either HealthCare.gov or one of the state-run exchanges.
Next week, the Supreme Court is set to hear arguments in a case that challenges the legality of financial assistance given to most customers of HealthCare.gov. Plaintiffs in that case argue that subsidies that help Obamacare customers pay their monthly premiums can only be awarded to customers of a state-run exchange, not one run by the federal government.
If the high court rules for the plaintiffs, the vast majority of Obamacare customers in the 37 states served by HealthCare.gov would lose billions of dollars in subsidies, and many of those people, experts predict, would then drop their health plans because they would become unaffordable.