MAR vs MDY: Correlation
Marriott International (MAR) and SPDR S&P MidCap 400 ETF (MDY) show a strong relationship: their 3-year correlation of weekly returns is 0.61.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MAR and MDY?
On 3 years of weekly data the MAR/MDY correlation comes out at 0.61, strong. The past 12 months show a weaker link (0.45) than the 3-year average (0.61). The 5-year figure is 0.65, and annualized covariance runs at 249.9 %².
Within MAR's tracked universe of 40 assets, MDY comes in at #11 by 3-year correlation. Over the last 12 months MAR came out ahead by 14.0 percentage points (+32.3% against +18.3%). The rolling one-year correlation moved between 0.46 and 0.77 over the past three years, a moderate range.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
MAR vs MDY: side by side
| MAR (Marriott International) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +32.3% | +18.3% |
| 5-year return | +173.2% | +47.5% |
| Volatility (ann.) | 24.6% | 16.5% |
| Beta vs S&P 500 | 0.97 | 0.91 |
| Max drawdown (3Y) | -30.5% | -24.0% |
| Market cap | $92.3B | – |
| P/E (trailing) | 36.7 | – |
| Dividend yield | 0.76% | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | Consumer Discretionary | ETF · US Small & Mid Cap |
MDY, State Street Investment Management's Mid-Cap Blend fund, carries $26.5B under management, 400 holdings, a 0.23% expense ratio, a 1.02% trailing dividend yield.
Year-by-year returns
| Year | MAR | MDY |
|---|---|---|
| 2022 | -9.3% | -13.3% |
| 2023 | +53.1% | +16.1% |
| 2024 | +24.9% | +13.6% |
| 2025 | +12.3% | +7.2% |
| 2026 | +14.7% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MAR and MDY good diversifiers for each other?
To a limited degree. At 0.61 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
FAQ
What is the correlation between MAR and MDY?
Using weekly returns as of 2026-08-27: 0.61 over 3 years, with 0.45 over the last year and 0.65 over 5 years.
Is MDY a good diversifier for MAR?
To a limited degree. At 0.61 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
What does a correlation of 0.61 mean?
A reading of 0.61 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/mar-vs-mdy.json
Embed this badge (it refreshes with the data), with attribution:
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Related comparisons
Hubs: MAR correlations · MDY correlations
