A term used in association with additive aggregation methods. In the course of expressing the expenditures on basic headings in a common currency, additive aggregation methods value the expenditures at international prices, where an international price for a basic heading is defined as the average of the national prices for the basic heading prevailing in participating countries. The average may be weighted or unweighted, PPP adjusted or unadjusted. It may be an average of prices or an average of price structures.