DCO vs MDY: Correlation
Measured on weekly returns over the past three years, Ducommun Incorporated (DCO) and SPDR S&P MidCap 400 ETF (MDY) carry a correlation of 0.51, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are DCO and MDY?
On 3 years of weekly data the DCO/MDY correlation comes out at 0.51, moderate. Little has changed lately, as the 1-year reading of 0.56 lands near the 3-year figure. The 5-year figure is 0.56, and annualized covariance runs at 253.8 %².
Within DCO's tracked universe of 12 assets, MDY comes in at #5 by 3-year correlation. The last year tells two different stories: DCO led by 81.2 percentage points, +99.5% for DCO against +18.3% for MDY. Risk is not evenly split, since DCO carries 1.8 times the volatility of the other side.
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.
DCO vs MDY: side by side
| DCO (Ducommun Incorporated) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +99.5% | +18.3% |
| 5-year return | +248.0% | +47.5% |
| Volatility (ann.) | 30.0% | 16.5% |
| Beta vs S&P 500 | 0.78 | 0.91 |
| Max drawdown (3Y) | -23.5% | -24.0% |
| Market cap | $2.8B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 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 | DCO | MDY |
|---|---|---|
| 2022 | +6.8% | -13.3% |
| 2023 | +4.2% | +16.1% |
| 2024 | +22.3% | +13.6% |
| 2025 | +49.4% | +7.2% |
| 2026 | +93.3% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are DCO and MDY good diversifiers for each other?
Somewhat, no more. With 0.51 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between DCO and MDY?
The DCO/MDY correlation stands at 0.51 on a 3-year window (1 year: 0.56, 5 years: 0.56), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for DCO?
Somewhat, no more. With 0.51 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.51 mean?
On the −1 to +1 scale, 0.51 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
Use this data
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Related comparisons
Hubs: DCO correlations · MDY correlations
