The percentage of health care costs paid by the insurance plan for an average enrollee. The average number is calculated through the expected cost for the standard population under the health insurance plan. The standard assumptions and cost-sharing provisions are also taken into account when calculating the percentage. This value allows for health plans to be compared individually, however, the value does not contain premium costs paid by the enrollee. The value is only a representative of the population; it may not reflect the cost-sharing percentage for each individual.