(Bloomberg Politics) — The Congressional Budget Office (CBO) says the Patient Protection and Affordable Care Act of 2010 (PPACA) could become more affordable.

PPACA, or “Obamacare,” as it is commonly known, will cost 20 percent less than previously projected over the next decade, the CBO said Monday. The reason for the revised estimate is a result of a decline in the rate of health care inflation.

The CBO says there were 42 million uninsured people in the United States in 2014. Without PPACA, there could have been about 54 million uninsured people.

The agency estimates that the number of uninsured people could fall to 29 million to 31 million by the end of 2016. If PPACA coverage expansion programs were not in effect, the number of people uninsured at the end of 2016 could be about 24 million to 27 million higher, the CBO says.

In 2009, when the CBO was analyzing the bill that became PPACA, it predicted that bill could reduce the number of uninsured people to 24 million by 2019.

Through 2019, the PPACA insurance provisions will cost an estimated $571 billion, down from $710 billion in the CBO’s initial estimates, according to the CBO.

The news is not all good, however. By the year 2025, the CBO estimated that 31 million people would still not have health insurance. Based on higher-than-expected enrollment numbers, Medicaid and the Children’s Health Insurance Plan (CHIP) program will cost the federal government $851 billion over 10 years, or $59 billion more than previously forecast, the CBO said.

Meanwhile, the Supreme Court plans to take up King v. Burwell, a case that could keep the PPACA exchanges managed directly by the U.S. Department of Health and Human Services (HHS) from offering PPACA premium tax credits. If the court rules against the HHS exchanges, the CBO will need to revise the new cost forecast.

See also: CBO: Killing PPACA Would Be Expensive.

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