The American people have become familiar with ObamaCare’s failings: higher premiums, fewer choices and a more powerful federal health bureaucracy. Yet another important piece of health-care legislation, signed into law last year, has gone almost unnoticed.

The Medicare Access and CHIP Reauthorization Act, known simply as Macra, was enacted to replace the outdated and dysfunctional system for paying doctors under Medicare. The old system, based on the universally despised sustainable-growth rate formula, perennially threatened to impose unsustainable cuts in physicians’ fees.

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UnitedHealth Group Inc. is leaving California’s insurance exchange at the end of this year, state officials confirmed Tuesday.

The nation’s largest health insurer announced in April it was dropping out of all but a handful of 34 health insurance marketplaces it participated in. But the company had not discussed its plans in California.

UnitedHealth’s pullout also affects individual policies sold outside the Covered California exchange, which will remain in effect until the end of December.

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Two recently filed lawsuits illustrate continuing difficulties the administration faces in implementing the Affordable Care Act, particularly under the constraints imposed upon it recently by Congress. Specifically, the suits illustrate the legal difficulties for the administration created by Congress’ limiting of “risk corridor” payments—made to insurers with high claims costs—to amounts contributed to the risk corridor program by insurers with low costs. Last year, CMS announced that it would have only $362 million in contributions to pay out $2.87 billion in requested payments, and so would only pay out 12.6 cents on the dollar for payment claims.

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