EXP vs MDY: Correlation
How closely do Eagle Materials Inc (EXP) and SPDR S&P MidCap 400 ETF (MDY) trade together? Their weekly returns over three years give a correlation of 0.71, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are EXP and MDY?
Over the past 3 years, EXP and MDY moved with a correlation of 0.71, which is strong. Recent behaviour matches the longer record: 0.71 over 1 year against 0.71 over 3. Over 5 years the correlation is 0.72, and the annualized covariance of weekly returns is 409.0 %².
Among the 24 assets we track against EXP, MDY ranks #6 by 3-year correlation. Correlation aside, the last 12 months split them widely, with MDY ahead by 34.0 points (-15.7% versus +18.3%). Note the risk asymmetry: EXP runs 2.1 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
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.
EXP vs MDY: side by side
| EXP (Eagle Materials Inc) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | -15.7% | +18.3% |
| 5-year return | +29.5% | +47.5% |
| Volatility (ann.) | 34.8% | 16.5% |
| Beta vs S&P 500 | 1.21 | 0.91 |
| Max drawdown (3Y) | -44.7% | -24.0% |
| Market cap | $6.1B | – |
| P/E (trailing) | 15.6 | – |
| Dividend yield | 0.50% | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | US Listed | 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 | EXP | MDY |
|---|---|---|
| 2022 | -19.6% | -13.3% |
| 2023 | +53.6% | +16.1% |
| 2024 | +22.1% | +13.6% |
| 2025 | -15.9% | +7.2% |
| 2026 | -4.1% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
EXP represents 0.17% of MDY's portfolio, so part of any move in MDY is EXP itself, and the correlation between them is partly mechanical.
Are EXP and MDY good diversifiers for each other?
Somewhat, no more. With 0.71 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between EXP and MDY?
The EXP/MDY correlation stands at 0.71 on a 3-year window (1 year: 0.71, 5 years: 0.72), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for EXP?
Somewhat, no more. With 0.71 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.71 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: EXP correlations · MDY correlations
