Milliman has completed its second annual study of the total annual medical costs for a "Typical American Family of Four". The Milliman Medical Index (MMI) measures the average spending for such a family if covered by an employer-sponsored PPO program. It provides a benchmark by annually assessing the changes in those costs over a 5-year period. The MMI also examines the key drivers and the components of actual medical spending. The MMI breaks out and measures the rate of consumer (employee) spending and the rate of total spending for health care services in a given year.