Obama Says Young Adults Push Health Care Enrollment Above Targets

WASHINGTON — President Obama announced Thursday that eight million people had signed up for health insurance under the Affordable Care Act, and that 35 percent of them were under the age of 35, countering those who predicted it would attract mainly older and sicker people.

The final number exceeds by a million the target set by the administration for people to buy insurance through government-run health care exchanges. In addition, the number of young people signing up appears to have surged during the final weeks of enrollment.

“This thing is working,” Mr. Obama said. “The Affordable Care Act is covering more people at less cost than most people would have predicted a few months ago.”

The president’s remarks, delivered in the White House briefing room, amounted to a second victory lap after he announced two weeks ago that 7.1 million people had signed up for insurance during the initial enrollment period, which ended in March.

The administration extended the sign-up period by two weeks, until Tuesday, to accommodate late applicants, and the new numbers suggested that interest was running high.

While the number of younger applicants has risen, it remains below the level that some analysts believe is necessary for the long-term viability of the insurance marketplace. The administration said 28 percent of those who obtained policies were between the ages of 18 and 34; some analysts said the optimum level would be 40 percent.

Still, after a disastrous rollout because of a glitch-ridden government website, and the news last week that the secretary of health and human services, Kathleen Sebelius, would resign, the announcement on Thursday was further evidence that the president’s signature legislative initiative was enjoying a dramatic reversal of fortune.

Mr. Obama seized on the numbers to make his case that the law was a success, to challenge Republicans to drop their opposition to it, and to push states that have chosen not to carry out some of its provisions.

“I find it strange that the Republican position on this law is still stuck,” the president said. “They still can’t bring themselves to admit that the Affordable Care Act is working.”

Mr. Obama spoke after a meeting with state insurance commissioners at the White House, during which he shared some of the new enrollment numbers and demographic data.

Critics of the law have cautioned that the top-line numbers are not by themselves proof of success. In addition to the demographic composition of the people who obtain insurance, the number of those who were previously uninsured is important, since many could have been moved from plans that were canceled by the law.

Mr. Obama did not offer figures, but said, “All told, millions of Americans who were uninsured have gained coverage.” Later, he added, “We’ve got a sizable part of the U.S. population, for the first time, that are in a position to enjoy the financial security of health insurance.”

In the early months of sign-ups, the percentage of young people between the ages of 18 and 34 — who tend to be healthier — hovered around 25 percent. But as White House officials had predicted, many young people appear to have waited until the March 31 deadline neared to enroll.

Health experts have long warned that the state by state, competitive insurance marketplaces set up by the law could be severely undermined if the pool of customers who signed up were mostly sick or elderly. If that was the case, premiums could spike and insurance companies could choose to abandon the federal marketplaces.

The overall percentage of young people enrolled is not a guarantee that all of the insurance marketplaces across the country will work perfectly. Individual insurance companies will make decisions about what their premiums are based on the makeup of their own client list.

But the higher proportion of young enrollees is a strong rebuke to the critics of the Affordable Care Act, who had predicted that it would fail to attract younger, healthier customers to buy health insurance.

In the months ahead, insurance companies will assess the age and health of their customers as a way of determining their premiums for next year. Mr. Obama said he expected premiums to rise, as they have annually for years.

But White House officials said the overall cost of health care is rising more slowly than previous estimates by the Congressional Budget Office. And they said that the higher proportion of young people who have enrolled is likely to keep most premiums lower than they would otherwise have been.

“Health care spending has risen more slowly than at any time in the last 40 years,” Mr. Obama said.