proration

(countable, uncountable) In budgeting, the proportional distribution or allocation of parameters, such as noise power and transmission losses, among a number of tandem-connected items, such as equipment, cables, links, or trunks, in order to balance the performance of communications circuits.
(countable, uncountable) In a telephone switching center, the distribution or allocation of equipment or components proportionally among a number of functions, to provide a requisite grade of service.
(countable, uncountable) In the insurance industry, the act of taking money that is currently due from the insurance company and moving it to the patient, knowing that the dollar amount being moved is due from the patient as a deductible, coinsurance, or copayment amount.