The cost of insuring an American family of four with an employer-sponsored health insurance plan rose to $12,298 in 2008. The annual premium for an employee and one family member (known as an employee-plus-one plan) rose to an average of $8,535, while that for the employee only averaged $4,386. The portion of this cost paid by the employee averaged $3,394 for the family plans, $2,303 for employee-plus-one plans, and $882 for the single coverage plans.

In 2008, there were 62.5 million American workers covered by employer-based health insurance. Of these, just over half (52.1%) had single coverage plans -- for 31.5 million workers. Another 11 million had employee-plus-one plans and 19.9 million had family plans. Employee contributions varied substantially from one part of the country to another, with employees in Florida paying the most ($4,412) for a family plan and employees in Indiana paying the least ($2,472).

These data come from the Insurance Component of the Medical Expenditure Panel Survey (MEPS), a set of large-scale surveys of families and individuals, their medical providers (doctors, hospitals, pharmacies, etc.), and employers across the United States conducted under the sponsorship of the Agency for Healthcare Research and Quality (AHRQ). The Insurance Component is a survey of business establishments and governments that collects information on employer-sponsored health insurance, such as whether insurance is offered, enrollments, types of plans and premiums. This survey is conducted annually by the U.S. Census Bureau for AHRQ.