Open enrollment for the insurance exchanges created by the Affordable Care Act kicks off Tuesday, and there’s a good chance consumers logging on to compare plans will face some sticker shock.

Monthly insurance premiums for popular plans on HealthCare.gov are rising by 25 percent on average next year, according to government data. But the increases will be more dramatic in certain parts of the country, especially for consumers not receiving subsidies, the numbers show.

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The fourth open enrollment for health coverage under the Affordable Care Act opened Tuesday, a critical 90 days that the Obama administration hopes will boost participation and stabilize markets roiled by premium increases and insurer withdrawals.

HealthCare.gov and state equivalents began taking applications Tuesday morning from people signing up for individual health coverage and learning about their eligibility for subsidies. This year is especially critical because consumers so far have been sicker and older than expected, which has led to higher-than-anticipated costs.

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As premiums for Affordable Care Act (ACA) insurance plans skyrocketacross the country, the Department of Health and Human Services (HHS) appears to be spinning the bad news by noting that 2017 premiums are about what the Congressional Budget Office (CBO) expected they would be when the law passed in early 2010. However, CBO’s November 2009 estimate of future premiums involved significant and generally unforeseeable errors in key underlying assumptions having nothing to do with the ACA. A valid understanding of the ACA’s effect on insurance premiums would need to account for these errors.

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If you are wondering why the Obamacare exchanges are in so much trouble, a whole slew of “experts” think they have the answer. From President Obama to health insurance industry CEOs to the editors of The New York Times to health policy gurus everywhere – the verdict is almost unanimous. Not enough young and healthy people are buying health insurance.

So, what’s the solution to that problem? Carrots and sticks, according to the conventional wisdom. We need to make health insurance more attractive to the young.

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Republican presidential candidate Donald Trump vowed on Tuesday to summon Congress into a special session to end and replace the Affordable Care Act, as he portrayed the repeal of the contentious health-care law as a prime reason for voters to elect him.

In midday remarks in the battleground state of Pennsylvania, Trump went slightly beyond his previous promise to try to end the ACA, widely known as Obamacare, on the first day of a Trump administration. But his call for a special session puzzled many, as the current Congress is scheduled to reconvene after the election, and the new one will gavel in January, before Inauguration Day.

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Donald Trump turned from attacking Hillary Clinton over her emails to focusing on voters’ pocketbook issues Tuesday, denouncing President Barack Obama’s health-care law and the recent rise in individual insurance premiums.

The Republican presidential nominee renewed his call to repeal and replace the law known as Obamacare on the first day of the official sign-up period for coverage under the law, and in the wake of significant rate increases in many battleground states.

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Anthem Inc. said it may join other major U.S. health insurers in largely pulling out of Obamacare’s markets in 2018 if its financial results under the program don’t improve next year.

Anthem retreating from the Affordable Care Act would mean that almost all of the major American for-profit health insurers have substantially pulled back from the law. The other big insurers — UnitedHealth Group Inc., Aetna Inc. and Humana Inc. — have already scaled back, after posting massive losses. The retreats threaten to further destabilize coverage in the markets for individual coverage, known as exchanges, that provide insurance to millions of Americans.

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