DAL vs MDY: Correlation
How closely do Delta Air Lines (DAL) and SPDR S&P MidCap 400 ETF (MDY) trade together? Their weekly returns over three years give a correlation of 0.58, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are DAL and MDY?
Over the past 3 years, DAL and MDY moved with a correlation of 0.58, which is moderate. Lately the two have moved closer together, with the 1-year correlation at 0.68 versus 0.58 over 3 years. Over 5 years the correlation is 0.63, and the annualized covariance of weekly returns is 351.5 %².
Among the 33 assets we track against DAL, MDY ranks #12 by 3-year correlation. The last year tells two different stories: DAL led by 15.6 percentage points, +33.9% for DAL against +18.3% for MDY. This link changes with the market regime, having swung between 0.24 and 0.75 on a rolling one-year basis. One caveat on sizing: DAL is 2.2 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
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.
DAL vs MDY: side by side
| DAL (Delta Air Lines) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +33.9% | +18.3% |
| 5-year return | +110.6% | +47.5% |
| Volatility (ann.) | 37.1% | 16.5% |
| Beta vs S&P 500 | 1.17 | 0.91 |
| Max drawdown (3Y) | -47.9% | -24.0% |
| Market cap | – | – |
| P/E (trailing) | 13.8 | – |
| Dividend yield | 0.94% | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | Industrials | 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 | DAL | MDY |
|---|---|---|
| 2022 | -15.9% | -13.3% |
| 2023 | +23.0% | +16.1% |
| 2024 | +52.0% | +13.6% |
| 2025 | +16.1% | +7.2% |
| 2026 | +17.8% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are DAL and MDY good diversifiers for each other?
Somewhat, no more. With 0.58 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between DAL and MDY?
The DAL/MDY correlation stands at 0.58 on a 3-year window (1 year: 0.68, 5 years: 0.63), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for DAL?
Somewhat, no more. With 0.58 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.58 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: DAL correlations · MDY correlations
