Hospital and medical expense policies were introduced during the first half of the 20th century. During the 1920s, individual hospitals began offering services to individuals on a pre-paid basis, eventually leading to the development of Blue Cross organizations in the 1930s. The first employer-sponsored hospitalization plan was created by teachers in Dallas, Texas in 1929. Because the plan only covered members' expenses at a single hospital, it is also the forerunner of today's health maintenance organizations (HMOs).
The United States health care system relies heavily on private health insurance, which is the primary source of coverage for most Americans. As of 2012 about 61% of Americans had private health insurance according to the Centers for Disease Control and Prevention. The Agency for Healthcare Research and Quality (AHRQ) found that in 2011, private insurance was billed for 12.2 million U.S. inpatient hospital stays and incurred approximately $112.5 billion in aggregate inpatient hospital costs (29% of the total national aggregate costs). Public programs provide the primary source of coverage for most senior citizens and for low-income children and families who meet certain eligibility requirements. The primary public programs are Medicare, a federal social insurance program for seniors and certain disabled individuals; and Medicaid, funded jointly by the federal government and states but administered at the state level, which covers certain very low income children and their families. Together, Medicare and Medicaid accounted for approximately 63 percent of the national inpatient hospital costs in 2011. SCHIP is a federal-state partnership that serves certain children and families who do not qualify for Medicaid but who cannot afford private coverage. Other public programs include military health benefits provided through TRICARE and the Veterans Health Administration and benefits provided through the Indian Health Service. Some states have additional programs for low-income individuals.
The Commonwealth Fund completed its thirteenth annual health policy survey in 2010. A study of the survey "found significant differences in access, cost burdens, and problems with health insurance that are associated with insurance design". Of the countries surveyed, the results indicated that people in the United States had more out-of-pocket expenses, more disputes with insurance companies than other countries, and more insurance payments denied; paperwork was also higher although Germany had similarly high levels of paperwork.
Co-payments were introduced in the 1980s in an attempt to prevent over utilization. The average length of hospital stay in Germany has decreased in recent years from 14 days to 9 days, still considerably longer than average stays in the United States (5 to 6 days). Part of the difference is that the chief consideration for hospital reimbursement is the number of hospital days as opposed to procedures or diagnosis. Drug costs have increased substantially, rising nearly 60% from 1991 through 2005. Despite attempts to contain costs, overall health care expenditures rose to 10.7% of GDP in 2005, comparable to other western European nations, but substantially less than that spent in the U.S. (nearly 16% of GDP).
The share of Americans without health insurance has been cut in half since 2013. Many of the reforms instituted by the Affordable Care Act of 2010 were designed to extend health care coverage to those without it; however, high cost growth continues unabated. National health expenditures are projected to grow 4.7% per person per year from 2016 to 2025. Public healthcare spending was 29% of federal mandated spending in 1990 and 35% of it in 2000. It is also projected to be roughly half in 2025.