/**
 * Compound Interest is the interest calculated on the initial principal and also on the accumulated interest of previous periods of a deposit or loan.
 *
 * @see http://www.investopedia.com/terms/c/compoundinterest.asp
 * @param rate
 * @param numOfCompoundings
 * @param principal
 * @param numOfPeriods
 * @returns
 */
export declare function CI(rate: number, numOfCompoundings: number, principal: number, numOfPeriods: number): number;