The 18- to 34-year-olds who helped elect Barack Obama could consign his signature domestic policy achievement to failure.

That’s because not enough millennials have signed up for Obamacare to make it work well. Despite repeated outreach — including entreaties from all manner of celebrities, including NBA stars and Obama himself — young people make up less than 30 percent of Obamacare customers. he White House had set a goal of 40 percent in that age bracket to sustain a healthy marketplace because millennials tend to be healthier and, therefore, balance the costs of sicker, older customers.

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Former President Bill Clinton attacked President Barack Obama’s signature health care legislation Monday, calling it a “crazy system” that “doesn’t make any sense” during a Michigan campaign event for Hillary.

“It doesn’t make any sense. The insurance model doesn’t work here,” Clinton said about the government-run marketplaces Obamacare set up. Clinton said that Obamacare “works fine” for people with “modest” incomes or who are eligible for government subsidies, or Medicare. But he added that, “the people that are getting killed in this deal are small business people and individuals who make just a little too much to get any of these subsidies.”

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Federal auditors ruled on Thursday that the Obama administration had violated the law by paying health insurance companies more than allowed under the Affordable Care Act in an effort to hold down insurance premiums.

Some of the money was supposed to be deposited in the Treasury, said auditors from the Government Accountability Office.

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If policy makers want to instigate more competition in the ACA, they can start by broadening “credibility adjustments” to make it easier for new plans to get started. The exemptions should cover all new carriers that enter the exchanges. They should be deeper and apply for an extended period over which a new carrier faces high startup costs.

A far better alternative would be to scrap the caps on health plan operating margins altogether, and make it easier for new plans to channel revenue into startup costs and investors to turn profits off these investments. The law already provides some flexibility toward these ends. It states that the HHS Secretary can adjust the individual market cap if “the Secretary determines that the application of the 80% may destabilize the individual market in such State.” So long as consumers have transparency (and reliable metrics) on the value of the benefits that different plans offer, the exchanges would benefit from giving new health plans far more flexibility on how they allocate their capital.

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