CSTM vs MDY: Correlation
Constellium SE (CSTM) and SPDR S&P MidCap 400 ETF (MDY) show a moderate relationship: their 3-year correlation of weekly returns is 0.58.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CSTM and MDY?
Across a 3-year window, the weekly returns of CSTM and MDY correlate at 0.58, moderate. Lately the two have moved closer together, with the 1-year correlation at 0.70 versus 0.58 over 3 years. Stretching to 5 years gives 0.59, with an annualized covariance of 392.1 %².
Few assets follow CSTM as closely as MDY, which ranks #2 of 11 tracked partners. Their recent paths diverged sharply: over the last 12 months CSTM outperformed by 69.4 percentage points (+87.7% for CSTM against +18.3% for MDY). Risk is not evenly split, since CSTM carries 2.5 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.
CSTM vs MDY: side by side
| CSTM (Constellium SE) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +87.7% | +18.3% |
| 5-year return | +38.2% | +47.5% |
| Volatility (ann.) | 41.2% | 16.5% |
| Beta vs S&P 500 | 1.25 | 0.91 |
| Max drawdown (3Y) | -66.3% | -24.0% |
| Market cap | $3.7B | – |
| P/E (trailing) | 7.0 | – |
| 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 | CSTM | MDY |
|---|---|---|
| 2022 | -33.9% | -13.3% |
| 2023 | +68.7% | +16.1% |
| 2024 | -48.5% | +13.6% |
| 2025 | +83.5% | +7.2% |
| 2026 | +45.4% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CSTM and MDY good diversifiers for each other?
Only partially. A correlation of 0.58 means CSTM and MDY share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
FAQ
What is the correlation between CSTM and MDY?
Using weekly returns as of 2026-08-27: 0.58 over 3 years, with 0.70 over the last year and 0.59 over 5 years.
Is MDY a good diversifier for CSTM?
Only partially. A correlation of 0.58 means CSTM and MDY share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
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: CSTM correlations · MDY correlations
