Patient Protection and Affordable Care Act The Patient Protection and Affordable Care Act, also the Affordable Care Act or colloquially known as Obamacare, is a United States federal statute enacted by the 111th United States Congress and signed into law by President Barack Obama on March 23, 2010. Together with the Health Care and Education Reconciliation Act of 2010 amendment, it represents the U.S. healthcare system's most significant regulatory overhaul and expansion of coverage since the passage of Medicare and Medicaid in 1965. PPACA's major provisions came into force in 2014. By 2016, the uninsured share of the population had roughly halved, with estimates ranging from 20 to 24 million additional people covered. The law also enacted a host of delivery system reforms intended to constrain healthcare costs and improve quality. After the law went into effect, increases in overall healthcare spending slowed, including premiums for employer-based insurance plans. The increased coverage was due, roughly equally, to an expansion of Medicaid eligibility and to changes to individual insurance markets. Both received new spending, funded through a combination of new taxes and cuts to Medicare provider rates and Medicare Advantage. Several Congressional Budget Office reports said that overall these provisions reduced the budget deficit, that repealing PPACA would increase the deficit, and that the law reduced income inequality by taxing primarily the top 1% to fund roughly $600 in benefits on average to families in the bottom 40% of the income distribution. The act largely retained the existing structure of Medicare, Medicaid and the employer market, but individual markets were radically overhauled. Insurers were made to accept all applicants and charge the same rates regardless of pre-existing conditions or demographic status (except age). To combat the resultant adverse selection, the act mandated that individuals buy insurance (or pay a fine/tax) and that insurers cover a list of "essential health benefits". Before and after enactment PPACA faced strong political opposition, calls for repeal and legal challenges. In National Federation of Independent Business v. Sebelius, the Supreme Court ruled that states could choose not to participate in PPACA's Medicaid expansion, although it upheld the law as a whole. The federal health exchange, HealthCare.gov, faced major technical problems at the beginning of its rollout in 2013. Polls initially found that a plurality of Americans opposed the act, although its individual provisions were generally more popular and the law gained majority support by 2017. Specific Provisions PPACA amended the Public Health Service Act of 1944 and inserted new provisions on affordable care into Title 42 of the United States Code. Few areas were left untouched. The individual insurance market was radically overhauled, and many of the law's regulations applied specifically to this market, while the structure of Medicare, Medicaid, and the employer market were largely retained. Some regulations applied to the employer market, and the law also made delivery system changes that affected most of the health care system. Not all provisions took full effect. Some were made discretionary, some were deferred, some collapsed after implementation and others were repealed before implementation. Insurance regulations: individual policies All new individual major medical health insurance policies sold to individuals and families faced new requirements. The requirements took effect on January 1, 2014. They include: Guaranteed issue prohibits insurers from denying coverage to individuals due to pre-existing conditions. States were required to ensure the availability of insurance for individual children who did not have coverage via their families. A partial community rating allows premiums vary only by age and location, regardless of preexisting conditions. Premiums for older applicants can be no more than three times those for the