The US health insurance market is highly concentrated, as leading insurers have carried out over 400 mergers from the mid-1990s to the mid-2000s (decade). In 2000, the two largest health insurers (Aetna and UnitedHealth Group) had total membership of 32 million. By 2006 the top two insurers, WellPoint (now Anthem) and UnitedHealth, had total membership of 67 million. The two companies together had more than 36% of the national market for commercial health insurance. The AMA has said that it "has long been concerned about the impact of consolidated markets on patient care." A 2007 AMA study found that in 299 of the 313 markets surveyed, one health plan accounted for at least 30% of the combined health maintenance organization (HMO)/preferred provider organization (PPO) market. In 90% of markets, the largest insurer controls at least 30% of the market, and the largest insurer controls more than 50% of the market in 54% of metropolitan areas.[116] The US Department of Justice has recognized this percentage of market control as conferring substantial monopsony power in the relations between insurer and physicians.[117]
States regulate small group premium rates, typically by placing limits on the premium variation allowable between groups (rate bands). Insurers price to recover their costs over their entire book of small group business while abiding by state rating rules.[74] Over time, the effect of initial underwriting "wears off" as the cost of a group regresses towards the mean. Recent claim experience—whether better or worse than average—is a strong predictor of future costs in the near term. But the average health status of a particular small employer group tends to regress over time towards that of an average group.[75] The process used to price small group coverage changes when a state enacts small group reform laws.[76]

Typically, employer-sponsored plans can include a range of plan options. From health maintenance organizations (HMOs) and preferred provider organizations (PPOs) to plans that provide additional coverage such as dental insurance, life insurance, short-term disability insurance, and long-term disability insurance, employer-sponsored health plans can be comprehensive to meet the insurance needs of employees.
Costs for employer-paid health insurance are rising rapidly: between 2001 and 2007, premiums for family coverage have increased 78%, while wages have risen 19% and inflation has risen 17%, according to a 2007 study by the Kaiser Family Foundation.[59] Employer costs have risen noticeably per hour worked, and vary significantly. In particular, average employer costs for health benefits vary by firm size and occupation. The cost per hour of health benefits is generally higher for workers in higher-wage occupations, but represent a smaller percentage of payroll.[60] The percentage of total compensation devoted to health benefits has been rising since the 1960s.[61] Average premiums, including both the employer and employee portions, were $4,704 for single coverage and $12,680 for family coverage in 2008.[58][62]
News Flash: The health insurance landscape has changed. Individuals who once could buy health insurance whenever they wanted are now forced to act like traditional company employees, and only enroll in a health insurance plan during an annual open enrollment period. However, life can throw curve balls, and leave an individual without health insurance outside…
In-Network Provider: (U.S. term) A health care provider on a list of providers preselected by the insurer. The insurer will offer discounted coinsurance or co-payments, or additional benefits, to a plan member to see an in-network provider. Generally, providers in network are providers who have a contract with the insurer to accept rates further discounted from the "usual and customary" charges the insurer pays to out-of-network providers.
In addition to such public plans as Medicare and Medicaid, the federal government also sponsors a health benefit plan for federal employees—the Federal Employees Health Benefits Program (FEHBP). FEHBP provides health benefits to full-time civilian employees. Active-duty service members, retired service members and their dependents are covered through the Department of Defense Military Health System (MHS). FEHBP is managed by the federal Office of Personnel Management.
^ Bump, Jesse B. (19 October 2010). "The long road to universal health coverage. A century of lessons for development strategy" (PDF). Seattle: PATH. Retrieved 10 March 2013. Carrin and James have identified 1988—105 years after Bismarck's first sickness fund laws—as the date Germany achieved universal health coverage through this series of extensions to minimum benefit packages and expansions of the enrolled population. Bärnighausen and Sauerborn have quantified this long-term progressive increase in the proportion of the German population covered by public and private insurance. Their graph is reproduced below as Figure 1: German Population Enrolled in Health Insurance (%) 1885–1995.
A 2011 study found that there were 2.1 million hospital stays for uninsured patients, accounting for 4.4% ($17.1 billion) of total aggregate inpatient hospital costs in the United States.[12] The costs of treating the uninsured must often be absorbed by providers as charity care, passed on to the insured via cost-shifting and higher health insurance premiums, or paid by taxpayers through higher taxes.[13]