How the Cost Score is built
A weighted blend of four cost categories, expressed as a single 0–100 composite where higher means more affordable for a North-American buyer — and honest about where the data runs out.
Housing · 40%
The heaviest single input is the Numbeo "Apartment 1BR, City Centre" monthly rent in USD. For countries this is the Numbeo country figure (served in USD where Numbeo serves it; native EUR recorded for the European markets); for Mexican cities it is the per-city Numbeo page, MXN converted at the disclosed X-Rates USD/MXN average. The Numbeo baseline is unfurnished — disclosed, not adjusted with a fabricated furnished premium. Mexico (country) keeps its originally-cited Inmuebles24/CFE-basis figure rather than re-basing to a Numbeo housing primitive that was never sourced; that instrument-basis difference is disclosed.
Food · 20%
The consistent cross-market instrument is the Numbeo Groceries Index (New York = 100, unitless). It is converted to a monthly dollar figure by a single disclosed anchor: Mexico's originally-cited food figure $460/mo divided by Mexico's Numbeo Groceries Index 46.6 gives $9.8712 per index-point, and every market's Food figure is its own Numbeo Groceries Index multiplied by that same factor and rounded. Mexico's Food figure is therefore unchanged by construction; national-statistics food baskets are cited only as directional corroboration. Tulum has no Numbeo page, so its Food figure uses the Mexico national index as a clearly-disclosed proxy.
Healthcare · 20%
The healthcare line is the WHO Global Health Expenditure Database out-of-pocket health expenditure per capita (current US$, indicator SH.XPD.OOPC.PC.CD), divided by 12. This is the average amount a resident pays out of pocket per person — it is NOT a private-insurance premium, and the earlier premium-based estimates are retired site-wide. The latest available year is used per country (2023 for most; Portugal and Italy 2024). Mexican cities inherit the Mexico national value as a disclosed national proxy, because no institutional sub-national health-spending series exists.
Daily living · 20%
For countries: Numbeo basic utilities (85m²) + 60Mbps internet + a monthly transit pass, in USD. For Mexican cities: utilities + transit only — Numbeo city pages publish no separate internet line, so the city Daily figure is a disclosed two-component basis. Tulum's Numbeo page carries no transit value, so its Daily figure is utilities only and the transit gap is disclosed, never filled with a fabricated number.
How the score is computed
The composite is a documented, deterministic formula — the four monthly inputs sum to a headline dollar figure, that figure is compared to a constant $4,240 US benchmark, and the ratio maps to a 0–100 affordability score through a fixed piecewise-linear band map. Higher means more affordable for a US buyer. Nothing is hand-graded.
Band map (vsUS → composite)
| v ≤ 0.40 | C = 100 − 50·v |
| 0.40 < v ≤ 0.55 | C = 80 − 100·(v − 0.40) |
| 0.55 < v ≤ 0.75 | C = 65 − 75·(v − 0.55) |
| 0.75 < v ≤ 0.95 | C = 50 − 100·(v − 0.75) |
| v > 0.95 | C = max(0, 30 − 120·(v − 0.95)) |
Grade bands: A 80–100 · B 65–<80 · C 50–<65 · D 30–<50 · F <30; ± by band thirds (A: A−/A only; F: plain F). Composite is rounded to one decimal place. Against the constant $4,240 anchor every market we cover is strongly affordable, so the letters cluster in the B+/A− range — the real differentiation lives in the headline dollar figure and the vsUS ratio, not the letter.
Disclosures
- Healthcare is WHO GHED out-of-pocket health spend per person (annual ÷ 12) — NOT a private-insurance premium. Latest year per country (2023 for six; PT/IT 2024).
- Grade compression: against the constant $4,240 US anchor every market is strongly affordable, so letters cluster B+/A−. The differentiation lives in headline$ and vsUS, not the letter.
- Mexico keeps its originally-cited Housing, Food and Daily figures (an Inmuebles24/CFE basis, a different instrument than Numbeo); the Food anchor is defined off Mexico's $460 so Mexico's Food figure is unchanged by construction. The difference in instrument basis between Mexico and the newer markets is disclosed.
- City Healthcare = Mexico national WHO GHED value (national proxy — no sub-national series). City Daily = utilities + transit only (2-component — Numbeo city pages publish no internet line).
- Tulum: Food = Mexico-country Groceries Index national proxy (no Numbeo Tulum page); transit uncitable (Numbeo blank → Daily is utilities only); Numbeo data oldest (Jan 2026). Ships with stacked disclosure.
- Belize: the Numbeo aggregate is only 13 contributors — ships with a prominent low-confidence caveat. San Miguel de Allende and Puerto Vallarta are low-confidence (17 Numbeo contributors).
- Numbeo housing is an unfurnished baseline; no fabricated furnished premium.