EFA vs MDY: Correlation & Overlap
How closely do iShares MSCI EAFE ETF (EFA) and SPDR S&P MidCap 400 ETF (MDY) trade together? Their weekly returns over three years give a correlation of 0.72, which is strong. By holdings, the two funds overlap 1.6% by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are EFA and MDY?
Over the past 3 years, EFA and MDY moved with a correlation of 0.72, which is strong. The relationship has been stable: the 1-year correlation (0.76) sits close to the 3-year figure. Over 5 years the correlation is 0.78, and the annualized covariance of weekly returns is 178.4 %².
Within EFA's tracked universe of 109 assets, MDY comes in at #36 by 3-year correlation. Twelve-month performance is nearly a tie, at +21.9% for EFA and +18.3% for MDY. On a rolling one-year basis the correlation drifted between 0.57 and 0.84, a moderate band.
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.
EFA vs MDY: side by side
| EFA (iShares MSCI EAFE ETF) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +21.9% | +18.3% |
| 5-year return | +56.7% | +47.5% |
| Volatility (ann.) | 14.9% | 16.5% |
| Beta vs S&P 500 | 0.77 | 0.91 |
| Max drawdown (3Y) | -14.1% | -24.0% |
| Dividend yield | 3.19% | 1.02% |
| Expense ratio | 0.32% | 0.23% |
| Assets under management | $78.0B | $26.5B |
| Sector / category | ETF · International | ETF · US Small & Mid Cap |
EFA, iShares's Foreign Large Blend fund, carries $78.0B under management, 666 holdings, a 0.32% expense ratio, a 3.19% trailing dividend yield. 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.
Portfolio overlap between EFA and MDY
The two portfolios are largely distinct. Weighing the shared positions, 1.6% of the two funds is identical, spread across 10 common holdings. That shared book is a large part of why the returns line up.
| Common holding | Weight in EFA | Weight in MDY |
|---|---|---|
| CFR | 0.56% | 0.28% |
| CSL | 0.26% | 0.40% |
| AAL | 0.27% | 0.25% |
| ALV | 0.88% | 0.23% |
| G | 0.19% | 0.16% |
| ORA | 0.15% | 0.17% |
| NXT | 0.11% | 0.36% |
| SN | 0.05% | 0.37% |
| CAR | 0.03% | 0.07% |
| AM | 0.03% | 0.21% |
Largest positions held only by EFA: ASML (2.99%), HSBA (1.57%), ROP (1.42%), SAN (1.38%), NOVN (1.28%). Only by MDY: TWLO (0.95%), P (0.94%), ILMN (0.93%), FTI (0.83%), ATI (0.80%).
Overlap = sum of the smaller of the two weights across common holdings, from issuer disclosures as of 2026-08-26. Top 10 common positions shown.
Year-by-year returns
| Year | EFA | MDY |
|---|---|---|
| 2022 | -14.4% | -13.3% |
| 2023 | +18.4% | +16.1% |
| 2024 | +3.5% | +13.6% |
| 2025 | +31.5% | +7.2% |
| 2026 | +14.3% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are EFA and MDY good diversifiers for each other?
To a limited degree. At 0.72 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 EFA and MDY?
The EFA/MDY correlation stands at 0.72 on a 3-year window (1 year: 0.76, 5 years: 0.78), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for EFA?
To a limited degree. At 0.72 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
How much do EFA and MDY overlap?
The two funds share 10 holdings amounting to 1.6% of weight, per issuer portfolio files dated 2026-08-26.
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Hubs: EFA correlations · MDY correlations
