BC vs MDY: Correlation
Brunswick Corporation (BC) and SPDR S&P MidCap 400 ETF (MDY) show a strong relationship: their 3-year correlation of weekly returns is 0.78.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BC and MDY?
Over the past 3 years, BC and MDY moved with a correlation of 0.78, which is strong. Recent behaviour matches the longer record: 0.78 over 1 year against 0.78 over 3. Over 5 years the correlation is 0.75, and the annualized covariance of weekly returns is 460.9 %².
MDY is one of the assets that tracks BC most closely: it ranks #1 out of the 58 assets we track against BC. Twelve-month performance is nearly a tie, at +21.7% for BC and +18.3% for MDY. One caveat on sizing: BC 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.
BC vs MDY: side by side
| BC (Brunswick Corporation) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +21.7% | +18.3% |
| 5-year return | -15.3% | +47.5% |
| Volatility (ann.) | 35.8% | 16.5% |
| Beta vs S&P 500 | 1.22 | 0.91 |
| Max drawdown (3Y) | -56.5% | -24.0% |
| Market cap | $5.0B | – |
| P/E (trailing) | – | – |
| Dividend yield | 2.18% | 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 | BC | MDY |
|---|---|---|
| 2022 | -27.1% | -13.3% |
| 2023 | +36.9% | +16.1% |
| 2024 | -31.8% | +13.6% |
| 2025 | +18.1% | +7.2% |
| 2026 | +6.2% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
BC represents 0.14% of MDY's portfolio, so part of any move in MDY is BC itself, and the correlation between them is partly mechanical.
Are BC and MDY good diversifiers for each other?
Only partially. A correlation of 0.78 means BC 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 BC and MDY?
Using weekly returns as of 2026-08-27: 0.78 over 3 years, with 0.78 over the last year and 0.75 over 5 years.
Is MDY a good diversifier for BC?
Only partially. A correlation of 0.78 means BC 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 0.78 mean?
A reading of 0.78 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: BC correlations · MDY correlations
