export type RatioEntry = {
    rank?: number;
    id: string;
    year: number;
    dept_name: string;
    position_name: string;
    work_location?: string;
    headcount: number;
    applicants: number;
    ratio: number;
};
export type RatioFile = {
    year: number;
    exam: string;
    snapshot_at: string;
    snapshot_kind: string;
    sources: string[];
    national: {
        total_applicants: number;
        qualified_applicants?: number;
        total_headcount: number;
        total_positions: number | null;
        avg_ratio: number;
        max_ratio?: number;
        max_ratio_position?: string;
    };
    top_positions_by_applicants: RatioEntry[];
    top_positions_by_ratio: RatioEntry[];
    notes?: string;
};
export declare function loadRatio(year: number): RatioFile | null;
export declare function availableRatioYears(): number[];
/** Build lookup map (year-scoped) from ratio file. Merges by_applicants + by_ratio. */
export declare function buildRatioMap(year: number): Map<string, RatioEntry>;
export declare function lookupRatio(map: Map<string, RatioEntry>, year: number, id: string, dept_name: string, position_name: string): RatioEntry | undefined;