import { PoolState } from '../types';
export declare class ExchangeRates {
    effectiveValueAndRates(state: PoolState, sourceCurrencyKey: string, sourceAmount: bigint, destinationCurrencyKey: string): bigint;
    getCurrentRoundId(state: PoolState, currencyKey: string): bigint;
    ratesAndUpdatedTimeForCurrencyLastNRounds(state: PoolState, currencyKey: string, numRounds: bigint, roundId: bigint): [bigint[], bigint[]];
    private _getRateAndTimestampAtRound;
}
export declare const exchangeRates: ExchangeRates;