hospitality.occupancy-adr-revpar

export function occupancyAdrRevpar(roomNightsAvailable: number, roomNightsSold: number, roomRevenue: Money): HotelPerformance

/** The three headline figures, each worked out from the raw totals. */
export interface HotelPerformance {
  readonly roomNightsAvailable: number;
  readonly roomNightsSold: number;
  readonly roomRevenue: Money;
  /** sold / available; 7500 = 75% */
  readonly occupancyBasisPoints: number;
  /** revenue / sold; null when nothing was sold */
  readonly adr: Money | null;
  /** revenue / available */
  readonly revpar: Money;
}

import { occupancyAdrRevpar } from "#fune/hospitality.occupancy-adr-revpar@^1";

import { roundDiv } from "./math_round_div.ts";  ← from math.round-div ^1.0.0 · built alongside by fune
import { type Money, money } from "./money_amount.ts";  ← from money.amount ^1.0.0 · built alongside by fune
import { type HotelPerformance } from "./hospitality_occupancy_adr_revpar_types.ts";

/**
 * Occupancy, ADR and RevPAR for a period.
 *
 * Each figure is divided out of the raw totals and rounded half-up once.
 * RevPAR is revenue over available rooms, not ADR times occupancy: multiplying
 * two figures that were each rounded already can be a penny out.
 */
export function occupancyAdrRevpar(roomNightsAvailable: number, roomNightsSold: number, roomRevenue: Money): HotelPerformance {
  if (!Number.isInteger(roomNightsAvailable) || roomNightsAvailable < 1) {
    throw new RangeError(`roomNightsAvailable must be at least 1, received ${roomNightsAvailable}`);
  }
  if (!Number.isInteger(roomNightsSold) || roomNightsSold < 0) {
    throw new RangeError(`roomNightsSold must not be negative, received ${roomNightsSold}`);
  }
  if (roomNightsSold > roomNightsAvailable) {
    throw new RangeError(`roomNightsSold (${roomNightsSold}) cannot exceed roomNightsAvailable (${roomNightsAvailable})`);
  }
  if (roomRevenue.minor < 0) {
    throw new RangeError(`roomRevenue must not be negative, received ${roomRevenue.minor}`);
  }
  return {
    roomNightsAvailable,
    roomNightsSold,
    roomRevenue,
    occupancyBasisPoints: roundDiv(roomNightsSold * 10000, roomNightsAvailable, "half-up"),
    adr: roomNightsSold === 0 ? null : money(roundDiv(roomRevenue.minor, roomNightsSold, "half-up"), roomRevenue.currency),
    revpar: money(roundDiv(roomRevenue.minor, roomNightsAvailable, "half-up"), roomRevenue.currency),
  };
}

Install

fune build

With that line in your source, in a TypeScript project (language typescript in fune.project), fune build resolves it and its 2 dependencies, pins them in fune.lock, downloads only the TypeScript package of each, and builds the code above into your project’s .fune/build, one readable file per capability with a header linking back here. Or pin a range in fune.project and build in one step:

fune add hospitality.occupancy-adr-revpar

The manifest, vectors and README with only the TypeScript implementation. Install it without the registry with fune add ./hospitality.occupancy-adr-revpar-1.0.0-typescript.fune, or fetch it from a terminal with fune pull hospitality.occupancy-adr-revpar@1.0.0:typescript.

The whole function, every language, is one file too: hospitality.occupancy-adr-revpar-1.0.0.fune, 15,023 bytes, sha256 a5b276ca41ec79434791e086583943b38f276c9e5b13ff990bce6edf2f1bfc4f. It installs into a project of any language.

// fune: before hospitality.occupancy-adr-revpar

// fune: after hospitality.occupancy-adr-revpar

// fune: replace math.round-div in hospitality.occupancy-adr-revpar
// fune: replace money.amount in hospitality.occupancy-adr-revpar

// fune: step hospitality.occupancy-adr-revpar after <n|label>

More from the author

## Why it is shaped this way

Each figure is divided out of the raw totals and rounded half-up once, to the minor unit or the basis point. RevPAR is *not* worked out as ADR x occupancy: both of those are already rounded, and multiplying rounded figures can land a penny away from the true value. ADR x occupancy is the identity to explain RevPAR with, not the way to compute it.

Room-nights, not rooms: a 100-room hotel over 30 nights has 3,000 room-nights available.

## What the caller decides

The industry definitions (STR's glossary, for example) leave choices to the operator, and this function takes the totals as given:

- whether out-of-order rooms come off the rooms available; - whether complimentary and house-use rooms count as sold (they add nights but no revenue, pulling ADR down); - what counts as room revenue. Use it net of VAT, and without breakfast, packages' food element or other extras, so figures compare across hotels.

## Errors

At least one room-night must be available; sold must be from 0 to available; revenue must not be negative.

Files