Antonio Galis, an insurance agent, discusses health plan options with a client in Miami, the day after 2016 open enrollment began under the Affordable Care Act. (Joe Raedle/Getty Images)

More than 11.3 million people have signed up for health coverage under the Affordable Care Act in all 50 states and the District of Columbia, according to data released Thursday that provides the first national snapshot of enrollment for 2016.

The total includes 8.6 million people (76 percent) through last Saturday in the 38 states using the federal marketplace, HealthCare.gov, as well as 2.7 million people (24 percent) who enrolled in coverage as of Dec. 26 in the 13 state insurance exchanges.

Enrollment is well ahead of the figures announced in late 2014, when more than 7.1 million people had signed up for 2015 health plans – 6.5 million via HealthCare.gov and 633,000 in the 14 states that were then running their own marketplaces.

“We’re seeing unprecedented demand" for coverage, Health and Human Services Secretary Sylvia Burwell said in a statement, which noted that the consumers now seeking coverage "are increasingly young, engaged and shopping for the best plan."

Nationwide, almost 4 million people under 35 signed up on the federal and state marketplaces through Dec. 26. Of those, nearly 3 million are ages 18-34 – more than a quarter of all plan selections. HHS officials touted that percentage, although it is about the same as late December last year.

The officials said one enrollment trend involving young adults was particularly encouraging.

“Over 1 million new consumers under age 35 signed up for HealthCare.gov coverage,” said Andy Slavitt, acting administrator for the Centers for Medicare and Medicaid Services. They represent 41 percent of all new consumers, he said, up from 38 percent at this time last year.

Federal officials also said the latest numbers show that consumers are actively engaged in choosing their coverage. Among the 8.2 million re-enrolled customers nationwide, more than half came back, reviewed their information and actively selected a plan.

And about 60 percent of people who actively re-enrolled through HealthCare.gov switched to a different plan, officials said. Many enrollees faced substantial premium increases if they stuck with their old plans and could save a substantial amount of money by switching, noted Larry Levitt, a senior vice president at Kaiser Family Foundation.

Robert Laszewski, an insurance industry analyst and frequent critic of the law, has warned that enrollment is not strong enough to make the ACA politically and financially sustainable.
“We always see these big enrollment numbers being announced by the administration, only to see the block shrink dramatically by year-end,” he wrote in a blog post this week.

Open enrollment continues through Jan. 31, and the sign-up totals could fluctuate as plan changes or cancellations occur, such as those in response to life changes like a new job or marriage. The data released Thursday only reflect plan selections and do not indicate how many consumers have paid their premiums to put coverage in effect.

Until now, the Obama administration's ACA snapshots have looked at just HealthCare.gov. Data released at the end of 2015 suggested enrollment was skewing slightly younger, and officials say that's likely a proxy for healthy people -- a trend that is crucial to the stability of the marketplaces.

Enrollment is a key barometer of the 2010 law's success because insurance premiums in the federal exchange are up this year by 7.5 percent on average, nearly four times as much as a year ago.

Despite the latest numbers, the Obama administration has not adjusted its modest projection for how many more Americans will have coverage at the end of the year compared to the close of 2015 – acknowledgement that successful outreach will be increasingly tough.

The decline in the nation’s uninsured rate was stagnant last year, according to a Gallup-Healthways Well-Being Index released Thursday. The survey showed that 11.9 percent of U.S. adults did not have health insurance in the final quarter of 2015, the same as in the first quarter.

“This validates concerns that similarly large reductions may not be possible in the future because the remaining uninsured are harder to reach or less inclined to become insured more generally,” Gallup noted.

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