import type { DayOfWeek } from '../constants';
declare type GetWeeksInYearOptions = {
    /** Use the UTC timezone */
    UTC?: boolean;
    /** Week 1 is definied as the week with the Gregoriain year's first [weekOneInclues] day in it */
    weekOneIncludes?: DayOfWeek;
};
/**
 * Determine the number of ISO weeks within a year
 *
 * @param input A date within the year, or a year number
 * @param __namedParameters see {@link Options}
 * @default weekOneIncludes Thursday
 * @return The number of weeks in the year (52 or 53)
 */
export declare function getISOWeeksInYear(input: Date | number, { UTC, weekOneIncludes }?: GetWeeksInYearOptions): number;
export default getISOWeeksInYear;