/** Elapsed duration and the next anchor to persist with accrued effects. */
export interface Accrual {
    elapsedMs: number;
    elapsedSeconds: number;
    anchorMs: number;
}
/** Elapsed time since a persisted anchor, capped once; persist anchorMs with the accrued result. */
export declare function accrueSince(anchorMs: number, nowMs: number, options?: {
    capMs?: number;
}): Accrual;